As long as the avatars are appropriate according to the forum rules, its good enough.
Sure, avatars are meant so that people can put a picture with their name or online ID or whatever.
Regardless, even if this is NOT a anime board, if people want to have naruto or a pokemon as an avatar, and it doesnt go against any rules they should be allowed to, anything else is just silly. Let people have whatever avatar they WANT to be represented by and associated with.
now, eat babies.