"Any kinky/BDSM pet peeves? If so, what are they?"
Well, Spanking Resource has a list I found myself totally nodding my head at, so go check out his list first.
What I would add? Stuff I've already pointed out: the prevailing idea that there is something wrong with people who like BDSM; the notion that Doms are naturally abusive, and Subs suffer from low self-image or an abusive past.
Also, the idea that if you're "into that sort of thing," you're into everything. A person who likes leather and pony play is not automatically into medical play or cosplay. A person who enjoys visiting clubs and watching scenes is not always one who likes to participate or experiment. People have their own personal limits, and they vary widely in the world of BDSM.
Also? (And this is a big one.) I hate how people think the way BDSM is portrayed in movies and on websites like Kink.com is how it is with everyone, in real life, who enjoy that level of kink in their lives. Actors are PAID to do certain things, to look and behave a certain way. It is a SHOW, complete with a soundstage and lights. It does not represent what goes on everywhere, and it should not be taken as an example of what people living the BDSM lifestyle are like all the time.