Going first thing in the morning is the best thing - for two reasons. First, the place in empty (which is something you rarely see at CEC!). Second, the staff has to test each game on the floor in the morning, and (at least at ours) they drop tokens in and leave any tickets hanging out of the machine. It's like an easter egg hunt for my kids finding all the random tickets hanging out of the games for the taking. They think it's great.
And ours does serve food anytime you want it. We will go at 9:00 for opening and buy a food package with tokens, but ask that our pizza be brought out at 10:30 for an early lunch. They have had no problem doing that for us.
We don't go often, but when we do, it has to be morning, because I would go crazy there at night. We went one week night last year because my sister's school had a fundraiser night there, and it was crazy. never again!