The problem with Citywalk is that ALMOST everything closes by like 10pm as well, except for a few locations.
The music automatically stops at the scheduled close time for CW for that day. Technically CityWalk doesn't close. You can get into it after hours. However, you won't be able to do anything unless you go to a still-open business, and don't even think that you will be able to walk around. After it "closes" security comes around and begins to flush people out.
None of the businesses have an enforced close time, but they all have an "encouraged" close time. But because getting visitors into the store after CW closes is so difficult, most just close the at the time CW does. I don't know what they could do to bring in more of a night-life to the place, but I feel like it would be tricky.
Take the concerts and DJs, for example. Those are quite popular, but do you ever wonder why they end early (around 9pm)? You guessed it! Noise complaints. Ever wonder why CW never has any of those loud-ass concerts anymore that would draw thousands to the venue to see semi-famous groups perform? Noise.
Part of the problem I think with CityWalk itself is that it is unable to do anything too late because of noise restrictions on it. If there's a concert going on and the place gets going but has to end at 9 or 9:30, people aren't going to walk around afterwords they're just going to leave. If there's a concert that starts a little bit later and ends a little later, it would become more of a late-night-type of event where people may go on a date to see it, eat at a restaurant then spend the rest of the evening watching it. Instead of arriving, walking around, watching the performance for a little, then leaving.
Just my observation.
-CW