Do you get your quarter back when you put the cart back in the cart line?
Our Aldi's has carts like that. When you get one out, you put in a quarter to get it unlocked from the next one. When you take it back, put the end of the chain in the quarter slot and get your quarter back.
I have seen grocery carts all over the place. It seems to me that if you get your quarter back, it is a great way for the store to control it's cart inventory. I am sure they aren't cheap. Less lost carts keeps our bottom line down.