Just my opinion, I don't think posting a link to somebody else's creation is necessarily spam, but it could be bad etiquette, depending on how and when it's done.
Posting direct links to your own creations on someone else's meme? That's definitely spam and against the terms. I think that's the pet peeve you might be thinking of.
Some users are ok with getting direct links from other users and want to see what their friends are up to, but personally I try to avoid doing that.
Posting a link to somebody else's particular creation over and over? I would say that's probably spam.
Promoting someone elses meme on your own creation? I would say that's never spam. In fact socrates has done exactly that, many times, kind of along the lines of what Beckett is suggesting. You can find most of those promotions using this tag
imgflip.com/tag/favorites