I'm so glad to see how many people CANNOT stand when people are smacking or cracking their gum. It irritates me to no end!! I'll try and explain this pet peeve to someone and they look at me like I'm crazy.
I can't stand scuffling feet and bouncy legs. I mean, I know its a habit to some that can't be broken but dang its ANNOYING!
Oh, of course chewing with your mouth open. It's just plain disgusting.
People who think whatever they have to say is more important then what you're saying and will either be so determined to say what they have to say they're not even listening to you or just plain cut you off.
When people come into my work (Subway) and ask me what kind of subs we have. Hello! We do have menus for a reason.
Then its the middle of the lunch rush, they've had about 10-15 minutes of waiting and they're just standing there talking to their co-works or whoever and then get up to order and tell me they need a minute....