>Who is really being inconvenienced?

The workers, drivers, and potentially future shoppers.

>I worked with at a grocery store loved going out and getting the carts.

You're getting the carts either way. I won't speak to if it helps to give you more time to yourself when collecting wayward carts, but there is some built in time for collections even with "good shoppers".

> if someone leaves their cart in a parking spot... well that is bad behavior

Yes, hence the shopping cart theory.

I'm not a perfect person but try to keep it out of parking those times I am tired. But I recognize that carts can still roll into the lot or that it increases risks of a future car who comes in.