I would only call it a dead casino in the sense that many of the minigames aren't that captivating by design. People definitely hang out there and do GATEs, play Mahjong, run Fashion Reports, etc. as other commenters have pointed out. A few extra mostly-unattended machines aren't in anyone's way.

Two suggestions that would improve it without adding actual gambling:
- Have an extra informational tab that saves your character's high score on the simpler minigames to give players an incentive to play those games besides the pithy amounts of MGP they award
- Add in-demand basic games like chess, checkers, etc. and/or a simpler version of Mahjong - I'm satisfied with the current offerings mainly because there's so many other things to do already