1. To catch up on all the amazing reality TV you're missing because you're wasting your time doing things like having drinks with people you match with on Tinder/Happn/(fill in the blank)
  2. To see the guy/girl you have a crush on but will never speak to because he/she is in so much better shape than you are
  3. It's a place where it's acceptable to look like you just rolled out of bed, as opposed to, say, the office
  4. The bath and body products in the locker rooms are nicer and more expensive than the ones you have at home
  5. It's an excuse to drink smoothies, which are, as everybody knows, milkshakes with a handful of kale thrown in