Unless I've got a ton of stuff, I really like the self checkouts. I don't always want to have to deal with slow cashiers and the like, and with groceries I prefer to bag myself to avoid things being smashed or squished.
I'm actually more surprised that more cashiers and baggers aren't upset about them, think about it. You used to have 6 cashiers and 3-4 baggers in a big store at any given time, now there are maybe 2 lanes, a bagger and one more cashier overseeing 4-10 self check lines. It's costing them jobs.