Hardly, the Cullens are more cliquey than the trio. Harry let Luna, Ginny, Neville and numerous others join their group the Cullens often stayed off on their own like a clique.

A family hanging out together is more of a clique than a group of friends hanging out together?

But I don't think cliques are wrong.

Not so much, no. They were closer to each other than anyone else but I don't think they excluded others (as zanhar1 said they still talked quite alot with Luna, Ginny & Neville for example)

Not really. Cliques, to me at least, are a group of people who want to hang out with each other and ONLY with each other. The Cullens were a bit like that. If you were to sit with some type of clique they'd look at you like "who's she?". Harry, Ron, and Hermione let almost anyone in their group ex. Neville, Luna, Ginny, Seamus, Dean you get the gist. I think Harry, Ron, and Hermione just had their group of friends but they were still open. Cliques don't let others in.

^ Exactly.

You can still be a family and behave cliquey. If that family only associates with each other for the most part it still is kind of clique. But that's just my opinion. About the trio hanging out together; isn't that normal, for friends to hang out with each other. The thing that separates their friendship from a clique friendship is that they let others talk to them and hang out with them as well.