Ah yes, the "I'm walking out, complaining loudly cause I didn't get served and couldn't wait couple more minutes. You just lost a customer, I'm never shopping here again" routine. I know we're understaffed and there are customers everywhere. Buddy, take it to management. It's out of my hands. I'm just the cashier.
I hand out business cards with corporate’s number and ask that they please complain to them as they are the ones not allowing us to have enough people working to adequately help all the customers. Hardly anyone calls. When they do I get a nasty call from our DM. I only get maybe one or two nasty calls a month so almost no one complains beyond the cashier level.