I recall reading an article a few years ago about RadioShack in that era. It said that employees weren't just rated according to how much they sold in total, but also by the
average amount of each sale.
So that cheap capacitor would have dragged down this employee's performance rating and compensation. It was better for him personally to ignore a capacitor disappearing out of the store than it would have been to ring it up and take your money.
I wish I could find the article; there was a story in it almost identical to yours.
In a way this reminds me of when HN used to track not just your total karma but also your average karma. If you cared about such things, it meant that every time you posted a comment you had to think not only about whether it was a worthwhile comment, but also whether you expected it to move your average karma up or down.
If you had an average karma of 10, then you wouldn't want to post a comment that you figured may only get 5 upvotes - even though those votes meant that five people appreciated your comment.
To me at least, HN seems like a friendlier place now that average karma is gone. And RadioShack would have made more money if they hadn't made their salespeople worry about lowering their average sale.
But, like some of the wacky schemes I've come up with, it must have seemed like a good idea at the time.