I can't say I've ever noticed a 'hugging culture' in the UK before, but certainly my daughter and her friends in the local music scene are always hugging each other!.
Nope. Only case is when hugs are going around and girls are present must you hug a guy. It's funny actually, I've noticed that all my guy friends only hug when they have come with their girlfriends, otherwise we just do the guy handshake. I am not sure what their reasoning is, however.