Union allows businesses to add a minimum tip to your bill even if you close out your tab. I bought a topo Chico (the only drink I ordered, $3.50) from a bar, gave the guy a dollar as a tip and then was charged an additional $2 through Union . I didn't authorize this tip, nor was it stated what the minimum tip is for a tab. Each bar should have to disclose what their minimum tip is before you pay, especially since it's not a walked tab. I'm glad this was only for a small bill, I couldn't imagine how much it would be had I gotten a couple of rounds. I'm deleting Union immediately and never using it again. There's so many bars in Austin, I don't need to patronize the ones that use this manipulative service. This happened at Bungalow on Rainey.