Restaurants already keep notes on their customers and refer to them whenever you call or make a reservation online. If you're a less-than-ideal customer, they won't do something as overt as refuse service (unless you did something truly horrible last time you were in), but they might be more likely to squeeze you in for a last-minute seating during a busy time if you've got some good things about you in the notes.
Maybe some restaurants. Not the one I worked at. And unless they share them in some kind of city-wide (or international) database, it's not the same effect as uber refusing to have you as a customer any more.
