Wait... are we not in a city or do you close early because it's fun to annoy me?

First off, please excuse the supercilious title, that's what happens when I am frustrated!

Question: What are the hours of operation in New York City?
Correct answer: Basically, 24 hours a day, 7 days a week

Logically, NYC operates all day because people are out and about all day. I don't believe anyone contests to this sort of arrangement we have going on.

Another question: What are the hours of operation in London?
Answer: Not open when you need it most.

This is a pet peeve I have with London. Everything closes unnecessarily early! I don't really have much to say on this matter and I cannot understand why it happens but I guess this is just a luxury we have in the US. Do you have any guess as to why this happens?