[throwthroyaboat]

Being gratuitously anti-social in a pub or supermarket already has consequences, name tags or not (you'll get kicked out). It doesn't matter if people know your name or not, they'll recognize your face, and you might not be welcome back.

Being gratuitously anti-social online might also have consequences (your account gets banned), but if creating another anonymous account is free and easy, then the consequences are trivially ignored.

You could make a distinction between anonymity and ease-of-creating-new-accounts, but usually the two are tied together.