Well, quite a lot of British youths are pretty obnoxious at home too(!) but never mind that right now. Why so many younger people get obnoxious abroad might have something to do with Britain's fairly rigid culture of misery and embarrasment. Freed from that environment, the British don't know what to do, and figure they must go to extremes in whatever they do because after all, who knows when they'll get a chance to act without consequences again? It's the same essential principle as that responsible for British tourists having a reutation for loutish behaviour, or, as Victoria Wood puts it, for "Fortysomething women seducing teenage Spanish waiters - it's almost as if it doesn't matter what he touches as long as he can't pronounce it!". . Having said that, it could go back even further, to a tradition that is centuries old - bad behaviour in someone else's country could be said to be responsible for the creation of the British Empire - "send the youngsters off and see what they bring back!" - and before that, young nobles raped and pillaged their way through territories in France in the years after Agincourt, simply because it was there and they felt no compunction to treat someone else's home with any respect.. Sound familiar?