they'll judge you personally for being slow instead.

If you're slow because you're old or disabled, it is what it is. I might even help if I'm up front.

If you're tired or something but clearly trying, it is what it is, people judging you are the dicks.

If you're on your cell phone, or not paying attention, or so incapable of reading that you have to call over a Walmart employee to tell you that yes, that says napkins on the monitor (actual thing I saw once and yes it's cuz she couldn't read, she said so): you deserve the judging.