I solved the problem of self checkout. I order most things and have them delivered to me. As far as the other reason Steve mentioned. My desk at work was kind of the focal point in the control room. A lot of my assistant operators liked to eat lunch at my desk. Then if I did not catch them, their feet would go up on the edge. I got them to stop by putting a sheet of paper taped to the front.
On it I wrote,"would you eat your lunch on the bathroom floor. Then don't put the bathroom germs on my desk". Did not have to tell many of them twice, after they thought about it.