Chris began his post by stating that it was sponsored by Izea, though it was not clear that the sponsorship was his getting the $500 card.
Sponsored posts aren’t new. For example an influential blogger may be given a computer or appliance to review. Many journalists would hold this compromises independence and so decline gifts or any sort. Most bloggers, on the hand, don’t have sponsoring organizations to buy them products. They may advocate a standard of full disclosure of any gifts or compensation.
Chris could have visited Kmart without spending $500 or indeed anything at all (unlike, say, a restaurant review). His post would have been different, but it could have been done with a $0 gift card.