Originally Posted by
1worldFlyer
How is that different from tipping a bar tender though? That's just as much a bribe in exchange for preferential treatment and/or larger servings of alcohol per drink as tipping an agent in exchange for the benefits you listed.
I don't see it that way at all because tipping a bartender is customary. But even if you look at it that way, tipping a bartender to get a bigger pour doesn't take away from the customer next to you.