Picky eaters. What I mean by this is people who claim they don't like a bunch of foods that every day normal people like, because when they were growing up their parents never made them try different things.
People who pee with the bathroom door open. The sound of urine hitting the toilet water is

to me, so when people do this it irks the hell out of me.
White people who call Curtis Jackson "Fiddy Cent" instead of "Fit-D Cent"
People who use "K" as a response in a text message. Not only is it gay sounding, but have we really become so lazy that we can't type the extra one letter to make it the proper "OK"?
People who think tipping isn't necessary. At the same time, bartenders and servers who complain about tips like they don't realize it is an option not a requirement. As someone who grew up in the bar industry it irks me when people leave no tip at all, but it irks me even more when bartenders (mostly female) complain about how shytty their tips were that night, but yet still made more in an 8 hour or less shift than people who do construction and other manual labor would in the same amount of time.
People who use credit/debit cards for everything. Actually, I have no problem with that per se, just the people who think cash no longer exists, and get pissed at you when they have to use it and say shyt like "I don't have any cash on me". Why don't you carry at least a 20 in your pocket for emergencies?.. and why are you copping an attitude about not having any, just hit the fukking ATM and keep it movin'.
People who like making small talk. Small talk makes me feel awkward because I can never come up with much to say. If we don't have a common interest or something to talk about, I'd prefer you don't try to force a conversation with a question like "So how about that weather out there?"