The idea of getting vending machines to accept PayPal seems ridiculous. What are the fees on a 0.65 cent candy bar? Does that leave any profit at all for the op

The idea of getting vending machines to accept PayPal seems ridiculous. What are the fees on a 0.65 cent candy bar? Does that leave any profit at all for the operator/owner of the machine? Or am I missing something there? I'm interested to know more about that 'hacking' of a Coke machine he is referring to. Anyone have a link?