Update: http://azizansari.com/tos says, All downloads are for use on one device only. You may keep one backup copy of the digital content downloaded from this site on any digital media of your choice.
Paying say $15 for an ebook that is nontransferrable, when the physical book is ALSO $15, is an absurdity that I can't imagine will stand the test of time. Our entire human history is on the side of the feeling that when you buy something, you can then give that particular thing away to someone else.
Current legal and market norms don't serve this basic human instinct yet, and it remains to be seen which shifts first. My money is on humans insisting to keep giving things away to their friends.
You point if fair though. I dont see why you've been down voted either.