I think those who are using the username as website name that should be removed or force them to change their username. This will decrease forum spam.
From a standpoint of aesthetics I can agree to a point. It looks awful but...this is an online marketing site. One can't be too repressive when members are simply trying to get some free advertising with their avatars/usernames right?
They are just like a GF which can be disappear at any time. Create 10 post or 20 post and afterward they will disappear (but some are permanent). I am just saying due to stop spam and useless post.
Easy solution, for signup, admin only have to force user to use either characters or numbers. if admin block symbols( dot . ) then they can prevent spamming for few percentage. As well, admin have to force new user to contribute something, before allowing to create new threads, their are many user who actually ask 1-2 question & then never even bother to came back!
Forcing a spammer to change their username probably isn't going to make them not spam... it will just make them spam with a less spammy username. I've definitely thought about limiting new usernames to alpha-numeric characters only, but of course that would only apply going forward.