Funny thing is the only time I have done this or see it happen is with aldi the only place around me that uses the cart deposit (although I wish everyplace did). Usually the person instigates by seeing you coming back and holds up the coin and then you exchange. The incentive is its a bit easier than having to mess around with the coin unlocking the system. With free carts though, unfortunately folks maybe bring them to the parking lot cart return carrals but at least half the folks just leave them whereever. I will usually grab one of the ones left around to get it out of the way and I don’t get why more folks don’t do that. Granted the people discarding them whereever are aweful but when I grab one of theres Im like. Im a saint. Anyway it saves you having to grab one when you get to the front but folks will walk by them in the lot and then get to the store and grab one from the area. People are strange.