This is the risk the airlines must face for charging a large premium on fully refundable tickets. But make no mistake, this man has taken the act to an extreme, and must live quite close to the airport . It's like skipping the last leg of an itinerary, it would likely be fine if done occasionally, but not everyday.

I recall that AF/KL have some minimal "admin" fee for refunding unrestricted fares, around $30, maybe it is to curtail free loungers.