Many of the above, in addition:
A group of (or even one) smokers just outside the door of a business or building. The smell is awful and it inevitably ends up inside the building, anyway!
I wish there were other places they could go, and if it weren't so invasive of my clean air, I would not care, but the smell really gets to me and I hate it all over my clothes and in my hair. Just reminds me of my crappy childhood and the selfishness of my mother/stepdads.
Spitting/chewing and spitting it on the ground indoors or outdoors where people will walk in it, or leaving half full soda cans or cups of spit-out tobacco (*barf*), etc. lying around.
Smokers that toss cigarette butts on the ground...do they not realize these don't biodegrade and they are UGLY? Gum chewers that toss their gum on the sidewalk, same as the smokers to me. Nasty habits. Litterbugs in general.
People that say they are going to do something then don't do it. Especially if it means I have to change my plans one way or the other and then when they don't do it, it further interferes with my schedule. I know it sounds very selfish, but I tend to get annoyed quickly when someone repetitively says "I'll do it" and I believe them, then they go back to doing what they were doing before and forget they said they'd take care of whatever they were going to do.
People that drive ten or twenty miles BELOW the speed limit where there are no passing lanes, and then when they DO come to a passing lane, all of a sudden they are Jeff Gordon. *sigh*
People that pay for advertising (signs, ads, etc.) and then don't bother to check the accuracy of their spelling and punctuation. To me it reflects on their business that they can't bother to represent themselves with professionalism. There are ways to have these things checked before committing them to the permanency of a billboard or painted or lettered sign. (for example, on a hair salon I recently saw: "Hair, nail's and tanning".
It bugs me! I know it is fairly inconsequential, but it gets to me.
There are more, but I'll leave them for others.
Liz M.