Because I'm one of those people that are so tempted to give you the real answer that you don't want to/don't expect to hear.
  1. "How are you?"
    Anything besides "I'm good, how are you?" and a smile on your face is unacceptable. Why is this a social greeting? Nobody truly wants to know how I am and it pisses me off to be greeted in this fashion. Just saying "hi" or even a small wave is enough.
  2. "How is everything tasting?"
    Again, anything besides affirming that your food is acceptable is frowned upon. They don't really want to hear that the food is awful, just not what you wanted, or overpriced compared to the quality.
  3. "How was your stay?"
    I have to ask this all the time as a front desk girl and frankly, I don't give a fuck how your stay was. I'm just hoping you don't complain so I don't have to pretend to care and give you an empty apology for whatever wasn't so great.
  4. Any variation of "Can you do me a favor?"
    I probably can, but I don't want to. Especially if you're interrupting something I was doing, and especially if it's outside the realm of things I enjoy doing.