Bill . Well, it sounds like things went well, even if the gig wasn't what you preferred to play ... There is a BIG difference in a performance where YOU are the attraction, as opposed to the 'wallpaper', but that doesn't mean you can't enjoy both ... As you said, this gig will help you improve your piano chops, so use it for that ... AND you can also make it more interesting for yourself by playing the same tunes with different styles/rhythmns ...
You should ask the management about advertising you as YOU want to be advertized ... If they are billing you as a 'jazz' player some less 'sophisticated' ( ) people may not want to go because of what they THINK you are going to play, and if you're not a jazz player, some jazz fans may be disappointed ...
I think I mentioned before that playing some of the more 'pop' stuff (Beatles/Elton John/Billy Joel)in bossa or latin styles often works very well ... the listener recognizes the tune, but the style fits in with the ambience of the restaurant ...

ALSO ... make sure you have your business cards prominently displayed and available ...

While Donny (with ALL due respect,God Bless him) might be in the position to turn down these types of gigs, others of us (for whatever reasons, including sheer lack of opportunity/market) may have to settle for slightly less than optimum in order to increase our following and demand ... and then who knows, maybe someday WE can turn down this type of work as well ... ...

Love ya Dnj !!!

Best of luck, Bill ... keep us posted ...
t.