In my town you can arbitrage them by buying quarts of yogurt at the farmers' market where the deposit is $1.25, and returning the bottles to the grocery store, that carries the same brand of yogurt in the same bottles, where they pay $1.50 for returns.
Reminds me how food stamps can be used to buy soda. Some people who had more than they needed would buy soda, pour it out, and return the bottle just for the deposit.
They fixed that by making the deposit not payable by the food stamp.
