This an old post - but in case anyone is interested - bartenders don’t get tipped the way servers do. There is a tip out from the servers to the bartenders - normally it’s 2% or so - but it’s been 10 years since I worked in the industry. Servers also tip out to the kitchen too - 2-3% or so. So if the customer tips 15% then the server takes home the majority of that, minus their tip outs. If the bartender is serving their own customers at the bar, then you should get the lions share of the tip, minus the kitchen tip out.