How is it open 24 hours yet I just got told at 2am that their kitchen is closed and will be for another hour and a half?

I can confirm that's it's just most-likely cleaning. Most 24 hour places pick the time when they deem it most-likely that people won't be there. I'm sure that you could still get beverages and hang out, though!

Hood cleaning likely. Has to be done by law. I know because i clean hoods. 24 hour places are hard to clean due to them being 24 hours. It's usually done before open or after close. Takes about 3-4 hours.