Well that really just depends on the economic theory you're using to weigh that question, since I think everyone would agree that a sandwich has far more tangible, intrinsic value than playing 20 questions on Skype. So, in that case: No, this guy's "rewards" aren't okay.
Nope. Not everyone would agree with that. At all. Value is assigned by what someone is willing to pay. I'd pay a shit load to Skype with some of my favorite artists.
This is one of the reasons eBay can exist.
What you're willing to pay != what everyone is willing to pay.