Of course there are plenty of swinger clubs in the city! My favorites are For You SwingerClub and Der Tempel (http://www.tempel.at/). They don’t have anything about wearing a condom or not in the rules, only the dress code. According to my experience, I believe it’s up to you and who you’re banging with. Though I don’t think anyone would apprechiate you slpping in your bare penis without asking first.