My pet peeves are
1): signs that are still up AFTER the event is over. Latest example is our local Elementary school who had their sign saying that school was going to be closed Nov. 25-27! I mentioned it out loud last night on our way home.... and today ---- it's gone! Finally.
2) Parents who don't watch their children while in a store, especially those who don't have the little ones strapped into the buggy. (37 years ago my niece fell out of a shopping cart and broke her clavicle! - now at age 40 she is a nurse!
3) Cell phone usage while with other friends, eating out, or anywhere else.