Self service checkouts

A recent survey has found almost a third of people using self service checkouts in supermarkets steal one or more items. The survey also found that the vast majority of those stealing items were not habitual shoplifters but normal customers who simply couldn't get the checkout to recognise an item, they simply gave up trying to get the item recognised and couldn't or wouldn't find an assistant to do the job. They then stole the item they needed, sometimes because they were too shamed to call for help and look stupid.
 Personally I can't stand the things.  The few times I've tried them they have failed virtually every time.
The words "unexpected item in bagging area" come up.
Curious that a loaf of bread or a bottle of milk is unexpected in a shop that sells food?  Maybe the supermarket doesn't really sell these items and someone has sneaked in and put two hundred bottles of milk there without being noticed?  Maybe, but my guess is the self service machines are total shit!
 The last time I used one it tried to mug me. No I'm serious! It kept about four pounds odd of my change.  I had to find an assistant and they had to get a manager, who then took the fucking piece of crap machine apart to get my change out. That took two people about twenty five minutes... how many people could they have served in that time with a proper check out???