"Clubs and bars have the band'ls start at 10 or later so they can open at 8 and sell more beer."
This. It's heavily dependent on the type of show (local artist vs. touring, etc.) but the economics of clubland are that you make all your money at that bar, not on gate. And if you say "move everything back," well, then people can't do the whole get home / shower / eat dinner / meet friends / drink / watch show.
You move away from that model by charging more for tickets, which then puts you into a different realm of artist, which then puts you in different venues, which ....