Because sometimes you don't have a choice
  1. At a restaurant
    DO shit where you eat! Restaurant bathrooms are soooo cool. And then when you get back to the table your food tastes so much better and you can eat more.
  2. At the gym
    One of the biggest perks of a multi-gym membership is access to toilets all over the city.
  3. At your friend's house
    If they are a close friend, you can do it talking with the door open.
  4. At an acquaintance's house
    Try it with the door open. You might become close friends.
  5. In a VIP poop trailer
    For fancy events. Make sure you push that foot pedal regularly and do not drink from the sink.
  6. At Starbucks
  7. At a nightclub
    You better bring a friend, because it looks like that door doesn't lock. Also a good time to do your drugs.
  8. On an airplane
    Especially when you open the door to a long line of angry people who all know what you did.
  9. In a regular port-o potty at a music festival
    Get your squatting legs ready and hold your breath as you contribute to that heaping mountain of human filth.
  10. In a fast food restaurant
    Garbage in, garbage out.
  11. At a gas station
    Is that a phone number on the wall? I mean I would never call it, but like, wouldn't it be funny? As a joke?
  12. In a tire on the side of the road
    Always keep toilet paper in your car. You never know.
  13. In the woods
    Get in touch with nature by touching nature...with your poop.
  14. In your pants as you struggle with your keys at your front door
    So close.
  15. Public Library
    Almost guaranteed to be both clean and empty
    Suggested by @zhao
    Suggested by @erichutchinson