My impression in Canada is that you don't see an awful lot of that yob type of thing going on, compared to what seems to be the case in Britain, judging from what I've seen on the box and from the frustration being expressed on this thread. I've been in and out of the city of Edmonton (northern Alberta) for the past twenty years, and for the last five years or so there have been problems occasionally on one three or four block strip of a street called Whyte Avenue, and acts of youth violence increasing in number and severity all over the city. There are several factors that I and many other people see as contributing to the increasing violence in Edmonton: traditional redneck/cowboy culture, disproportionate numbers of people aged 18-25 or so (come looking for work), groups of immigrant kids competing for turf, a lucrative drug trade, gangsta-rap culture, and a broader Albertan culture that seems lacking in any sorts of values other than "work hard, make as much money as you can & spend as much money as you can". Having said that, though, the trouble-makers are really the exception to the rule; most of the kids out getting soused on a Saturday night in Edmonton are just out for a good time, and in fact most of them tend to be quite personable after a half-dozen beers, if a little loud. And I think the same holds true for most Canadian communities.

My impression is that the whole business of the class system has created and feeds a great deal of animosity and alienation in Britain, and this gets expressed in yobbery ...

And here's a little anecdote that may interest you, being from Northern(?) Ireland (Divis, that is). In the late-seventies, I had a friend who had immigrated from Belfast. We were out for a Sunday drive one time, and stopped in a small town in rural Ontario. I noticed at one point that he seemed quite taken with a public flower garden/display in the center of town, which I had hardly noticed. He turned to me and said, "In Ireland you'd never see something like this in the small towns. The local kids would have it torn up the first weekend." Make of that what you will.