I suggest a compromise: Have tiny shops outside the main cities have operation hours. Say, one of the NPCs in Hyrstmill or Aleport close down for the night. Main cities though, their shops have to cater to adventurers. Would make more sense to keep the shops open 24/7 in a city.
Don't really need the entire world shutting down at the strike of 9pm (in game), but having NPCs exhibit a little bit of life would only add to the world. Then again, I can easily see how this would become an annoyance.
