Mass messages, mass comments, glitter comments, comments that use copyright-protected images... I delete 'em all. I haven't gone so far as to block anyone yet, though. It seems that most people who hit me up are only one-time offenders.
Glad you posted this Dottie because this is a definite heads up to anyone who may have missed it, but mass messaging is a BIG no no here on PL so if it does happen report that nonsense! I agree, it's rude and impersonal!