End the Shopping Cart Roundup
The Swedes, and perhaps elsewhere, have come up with a system that almost completely eliminates the all too common shopping cart roundup required at US grocery stores and malls.
The carts are linked together with a short chain both in the store and in parking lot storage. A small device on the handle has slots for two denominations of coins. Insert a coin into a slot and the cart is released for use. You get your coin back when you are finished shopping, return the cart (either in the store or a designated parking lot site), and clip the cart back onto the daisy chain. Inserting the clip on the chain pops out the coin.
Here the two supported coins are 5 sek and 10 sek — 5/7ths and 10/7ths of a dollar. Either one works.