I use the self-checkout at the local Walmart and have never, ever had anyone make me line up or stop me to check my receipt. Hell, one time I forgot about two six-packs of sodas I had stuck over the cart railing and walked out with them, when I checked my receipt at home I noticed I hadn't rung them up. Went back the next morning, explained it to Customer Service and paid for them then.
Keeping your karma straight - I appreciate that
For you all who don't like having your receipt checked, it's a loss prevention thing that helps keep prices low. Just because you don't steal doesn't mean nobody does.