Piano bar gigs can go to either extreme - from the never-seen-and-barely-heard variety to the lid-slamming stage antics of dueling pianos. I don't think we can pigeon-hole any one piano gig as an example of all piano gigs.

ALL of my gigs are "piano-bar" ("piano restaraunt" would be closer) but NONE of them are the wallpaper kind. I would consider my music to be "foreground music" - it's not background music since I mostly sit on a lighted stage with a dance floor like a band would. No vocals but people dance to my music - not loud enough to drown out conversation but loud enough to be heard throughout the building. This description fits fits all of the places I play, both regularly and occasionally. I would put them in the center of the extremes that piano gigs can go. I think the performer has some say in the kind of gig they wind up playing and the client has most of the say, but those are all negotiable.