Don't worry, you will stop feeling bad about it after it happens a few more times. You haven't done anything wrong.
This is beyond madness.
Raise the prices, get rid of tipping, it will make everyone happier.
2. Not only would spitting in food get you fired but it's also a crime. Do you really think it's common for people to be this reckless with their livelihood?
The most we would do is serve you slower if you're being a jerk.
I can't speak for every food service worker, but most FOH are too busy/indifferent to really care.