Some of mine...
When people call it an "ATM Machine"- M stands for Machine, so that's repetetive!
When people say "walla" instead of "voila"
When people leave their car at the gas pump when they go to pay, when the station is busy and there are lines of cars waiting to get to the pump.
Cell phones in book stores and the library! I was at the library yesterday, and a woman was applying for a card when her phone rang very loudly. The woman helping her told her she would have to turn it off while in the library, and the woman answered it anyway! When she hung up, the woman told her again about turning it off. A few minutes later, guess what! Her phone rings AGAIN! The clerk made her take it outside this time, but I dont think I would have been as polite as she was!