1. little kids going apeshit running around and screaming
2. when you go in by yourself and you say "one" and they go "just one?" in that fucking whiney voice like they clearly think you're pathetic because you happen to be eating by yourself, and...
3. when they put you at a shitty table because you're by yourself. I got stuck at one that was half occupied by the waiters' coffee maker once
4. waitresses who flirt with the male customers, especially when they do this right in front of the guy's wife or girlfriend, but they just slap the plates down in front of women customers like they don't give a shit
5. If I wanted mayo I would have ordered it. eurgh.