[rcxdude]

The scan as you shop thing seems to be pretty heavily audited, which really removes the point of doing it, since it just slowed things down. I think when I tried it I put up with it for about 4 out of the first 6 shops winding up slower than just going through the self-checkout or a regular one because of the extra faff.

[jon-wood]

I regularly do scan as you shop and have started to notice some patterns in auditing. If I change my mind on a product and remove it from the basket while shopping I'll get audited almost every time, similarly if I add a single onion (which is a weighed product) to my basket. I do enjoy the company line of asking "did you have trouble scanning anything" just before they do the check, which is blatantly a get out of jail free card to say "oh, yes, I did in fact have some trouble scanning that 42" TV that doesn't appear in the basket currently".