How to describe the "Chav", or Kev, Charver, Townie, Ned, Scallie, etc, to a foreigner.. not only in a different country but on a different continent, with all the cultural difference that entails.. Difficult.
I believe they may be more analogous the local villains you describe than you might realise, at least in terms of behaviour and thinking, except their violations tend to run more towards social crimes rather than out-and-out armed robbery (though there is still a fair bit of that)... mainly because they dont have guns.
They're just lower class lowlife scumbags who enjoy making life hell for other people and are just too thick to think of anything else. Go out, get drunk, and either f*ck someone or f*ck someone up, that's a good night out. Iniiit?
I dont know if you've ever had the opportunity to sample the british band Pulp, but their (now quite old) song Mis-Shapes tackled that subject quite well I think, from the standpoint of those who aren't particularly higher class or well moneyed, but sick of being kept down and having their quality of life ruined by those who make their money by dishonest means and then screw things up. Chavness is six parts social status and where you grew up/income based, but a good four parts independent from that - they crop up everywhere disguised as otherwise respectable, high ranking society members, not just on the council estates.
("Whats the point of being rich if you can't think what to do with it, because you're so bleeding thick?"
"We want the things you won't allow us - we won't use guns, we won't use bombs, we'll use the one thing we've got more of, that's our minds")
They most often DONT have jobs and have only had a superficial education - disrupting classes, bullying, skipping school through childhood and then dropping out early supposedly to "find a job" but really just to peddle fake rolexes - and are quite happy defrauding the benefit system and dealing in petty crime, wear glaring counterfeit copies of designer brands that were already in rather bad taste (before the recent Burberry and Von Dutch craze it was Tommy Hilfiger, Calvin Klein etc.. and before that monstrous fake fur coats, tracksuits* and puffy bomber jackets.. etc) normally as an expression of some kind of "individualism" that is actually more like a uniform or herd mentality, wear horrid fake-gold or plated jewellery (often from a discount home furnishings catalogue without even seeing the item for real before wearing it) - e.g. the sovereign ring or large diameter hoop earring etc, cant talk properly (its becoming a whole new language), have consistently violent and confrontational attitudes and take offense at everything on purpose, and even if they are smart tend to act quite thick - using hitting something and making a noise as an outlet for energy or anger rather than any kind of work or creativity. Basically the kind of person you can quite happily stop seeing as a person after about five minutes contact and instead a heavily annoying
thing that must be killed and removed from your life - if they havent actually made the first attack themselves.
They enjoy drugs, the poor/young ones hooked on cheap cider (like beer, but made out of apples so much less expensive, and only really enjoyable for the first two glasses - hope im not being too patronising here

) and horrible rough brands of cigarette, the older ones moving on to the ever present Carling lager. Those who find this stuff not strong enough then go quite quickly through hash to cocaine and heroin, amphetamines, pills, regardless of whether they can afford it, and naturally go on to cause even more trouble when jacked up, or trying to "borrow" some money to pay for their habit.
They drive Vauxhall novas and corsas, citroen saxos, peugeot 205s, ford orions and every kind of Fiat, always the low displacement models, with hugeonormous wings, bodykits, fake exhaust pipes, ugly graphics/paintjobs, cheap generic alloy wheels from the local expensive car parts retailer (characterised often by very thin spokes - less metal = cheaper..) and fit lexus lights and quad headlamps regardless of whether they suit the car. The more aspirational ones might graduate to ruining a perfectly good Golf GTi (any age). Playing some pretty rubbish, commercialised music. If it's not charting and not churned out by a pop factory, it aint worth listening to. Jimi Hendrix does not exist.
Their housing is the tower block (more New York tenament than classy high-rise apartment building) and the "Council Estate" - single-entrance access miniature towns of cheap housing built by local government in the 60s and 70s to give the less well off people somewhere to live either for free (on benefit) or cheaply (on low incomes) by renting direct rather than from a landlord. It kind of backfired, as all the scum naturally went to live there.. Burnt out cars littering the streets, roads with no windows, drug abusers openly shooting up, that kind of thing (ok maybe not that bad everywhere, but fairly grim and threatening places to live).
The problem of the situation is.... is it the upbringing? Is it the environment? Or something that's just inherent in a person's genes that disposes him or her into this kind of behaviour? It's hard to be sure... there'll be rotten apples everywhere of course, and there's more than likely far more people being terrorised on each estate or in each tower than are doing the terrorising - but it's starting to look like a disease of the whole tree.
Part of it seems to be a breakdown of general discipline in this country and a removal of a lot of the human face of the law and education to concentrate on the easier, more numerically quantifiable and mechanically enforcable kind of results - e.g. ploughing money into CCTV which may not give a decent picture or ever be watched instead of well trained security staff, speed cameras instead of proper driver training and police patrols, concentration on league-table boosting exam results at school rather than everything else... etc etc. The police are unwilling to attend anything but major crime scenes any more as they're badly understaffed (and so when they are having an easy time, this leads to a rebound where laziness sets in), if you get robbed or attacked it seems a weapon and a mother with child probably has to get involved before they'll put the blue lights on their car to get to you quickly (the patrol unit that came to my "aid" was driving so leisurely that i could cycle quicker - good job the crazy woman didn't come back with a knife!). Police can get sued for putting handcuffs on a murderer too tightly, farmers have gone to prison for shooting at persistent burglars after being told the police can't do anything about it, parents won't be allowed to chastise their children anything other than verbally any more if certain "liberal" (ha!) groups get their way (i've seen the results of a house that runs on shouting rather than punishing the children with a short, painful but non-damaging slap on the backside or taking toys/food away - the results aren't pretty and are
loud), teachers can get in trouble for going even so
far as to shout ----- so on and so forth. There's no holdbacks any more and perhaps chav-ism is just a signal of impending anarchy.
Oh and they love football, or at least pretend to in huge swathes as an excuse to go abroad and hit foreigners.
*ok, the shiny polyester tracksuit and white baseball cap havent actually ever gone away... just become less gaudy of late, probably because of dayglo inks no longer being affordable or something.
Hope thats of some use, I know it's long, but that should give a good explanation.