I absolutely fucking hate how in most shops you are not allowed to cancel an item without a shop assistant. What's even the point of it being a "self"-checkout? People are not here to rob you, for fuck's sake, they just accidentally scan an item twice sometimes.

I asked an assistant once why it is designed this way, and she said something along the lines of "what would stop customers from scanning a bunch of items and then cancelling them and not paying for them?" Bitch, if someone wanted to steal something, they could just not scan it in the first place!

Or, you know, just walk out. It's very likely nobody would stop them.