First off, the vast majority of men who come to LOS in the winter are European.
Secondly, we are not angels, but by and large, Americans drink a lot less alcohol, especially hard liquor, but also beer, than Europeans. In America, very few people over the age of 30, and for many, over the age of 25, drink with the intent to get drunk. The idea is to get a little intoxicated, a social buzz, if you will, and then drink just enough to keep it from wearing off. The East Coast is a little different, but in California, even most teenagers drink just to get a little high, not to get ridiculously pissed. It is not socially acceptable in America for a mature adult to get stinking drunk in public. In America, a bartender is prohibited by law from serving drinks to anyone who is already very drunk, and can be held responsible for any problems caused by that person if he serves them another drink. I would think in a lot of the groping cases, alcohol has a lot to do with that behavior.
Third, as it has been pointed out in a previous post, these Neanderthals are not groping the farang women. The mentality of many Europeans(and this is what I have learned only here on this Board from what BMs say about their countrymen/women) is that Thai women are wh0res, and may be looked upon and treated differently from other women. Americans do not have preconceived notions about Thai women and therefore are inclined to treat them the same as farang women.
I can't comment on Aussies. Middle Eastern and other Arab men, and Islamic men, and Indian men have a reputation of being even worse than Europeans from what I have been told by Thai women. Of course, that does not apply to all of them, either,as many, or perhaps most, are probably gentlemen, as are most European men, too. But there are far more Euro tourists here.