McDonald's: The can currency
In Sweden an empty drinks can is worth one kronor when you recycle it. At music festivals and in parks you’ll find a lot of young people with empty drinks cans and empty wallets. So to help them and help the environment McDonald’s accepted cans as a currency. Just take a bag, fill it with your empty cans and exchange it for burgers. McDonald’s then exchanged the cans for cash at the recycling depot.