I rarely get group spammed, but it happened to me before. So now I make my own group, usually called "hell no" or "not joining your group". With a silly bio.
I think it's very annoying to get spammed with group requests. You have to decline them all, and imagine if you misclicked on accept... UGH.
I don't cuss on the person who sent them, though (being on SB and not knowing who sent it, anyway), but I usually post a kindly warning in local, without mentionning the group. They recognize themselves and stop, while others avoid doing the same mistake. ovo