I was just wondering what does class Indecent exposure as???
About 2 months ago myself a few friends and the wife where out in Zurich on a saturday Night and end up in a bar late at night, We was in a bar where there was a couple og guys wearing kilts one of them working there, when we where about to leave the guy lifted the kilt and exposed himself to our group which i thought was totally out of order and wrong, but the people at the bar drinking with him all laughed and thought it was funny. I found this totally rude and wrong especially in a place of work.
In all seriousness it's difficult to say whether this should offend you or not - your profile only gives your location as Zürich. As a result we don't know where you come from, and therefore have no idea if this behavior is taboo in your place of origin or not.
Having said that, if your culture holds this behavior as taboo, then I'm afraid you are going to have to adapt. The behavior you describe is a bit naughty, but in no way taboo, and quite frankly not to be unexpected from tipsy kilt wearers