I'm glad to hear you're thinking of adding a PS3/4 system to your bar. The increase in patronage will probably be noticeable, but keeping the system(s) running can be hard. I mean...I have a hard time just keeping my own PS3 at home working properly (I have cats and they clog the PS3 with their hair on purpose, I think, and I'm always losing where I put my games). On top of this, cleaning your PS3 controller can be a hassle.
In the old days of the NES and SNES, you could pretty much spill whatever you wanted on them, and they would still work fine. If you did manage to get liquid inside, it was four screws away from being cleaned out with some isopropyl alcohol.
I recently had to take one of my PS3 controllers 'to the cleaners'. At sometime in the recent past, I had gotten some sticky liquid near the PS button. A portion of this liquid had breached the outer hull of my PS3 controller, and the PS button would just stick. This could result in the PS3 thinking I was holding the button down, and the system would reset or turn off. I managed to get the controller apart (no small feat, as many of the buttons have springs and little pieces attached to them) using the iFixit guide. I finally got down to the PS3 button, pulled it out and washed it off. I re-assembled the whole controller, excited about using it again. The PS button didn't even get one good use. It appeared I had failed to clean it well enough and the darn thing still sticks (all the time).
The moral of the story is that there isn't an easy way to clean a PS3 controller. They're very delicate mechanical and electronic components. I would recommend using inexpensive third-party controllers that you won't mind replacing every once in a while and just wiping them down with Clorox wipes every night. Heck, you could probably pay someone a few bucks to 'deep clean' them once every three months or so anyway.