In the "Notice of Interpretation with Request for Comment", the FAA defined "delivering packages to people for a fee" as non-hobby, non-recreational drone activity.
Amazon, who said it intends to start a drone delivery program, had a potential loophole as their shipping is free for Amazon Prime subscribers and therefore is not a fee. The FAA foresaw this and wrote specific language in the regulation, tightening the loophole.
"If an individual offers free shipping in association with a purchase or other offer, FAA would construe the shipping to be in furtherance of a business purpose, and thus, the operation would not fall within the statutory requirement of recreation or hobby purpose."
Amazon is years away from developing the delivery drones so there is currently no conflict.