Giving bartenders a dollar no matter the order amount is not cool, really. That’s how you turn invisible to them the next time you want to order a drink ;)
Most people run tabs on plastic nowadays, so how's the bartender supposed to even know what they are earning per drink? I prefer to pay in cash & tip dollars as I go, & i find most bartenders are more than happy to get them & continue good service when they see paper coming their way on every transaction.