It's a system that was never introduced in the US, and in fact I've never even heard of it until now. So surely one option is to remove the system altogether.
That written, I'm also surprised there's any serious talk of going cashless there. We have plenty of cash-only businesses here that preclude any serious consideration of the notion.
You apparently have never shopped at Aldi. You need a quarter to get a cart. When you take the cart back and lock it into the carts then you get your quarter back.
That's probably why in the US nobody put their cart back. They would do it if they had to get their coin back. Again, to fight laziness, go for the wallet!
That written, I'm also surprised there's any serious talk of going cashless there. We have plenty of cash-only businesses here that preclude any serious consideration of the notion.