But don't you need to leave the house to return the items? I've always regarded dropping off and mailing packages to be a huge chore.
However, I buy so much from the (I'm a Prime member) the I almost always have a small box around. I just put the item in it, print out the pre-paid shipping label, and drop the box in a UPS box or at a UPS store. It's not that bad.
I can order by 9AM and, for just $3.99, have it delivered that same day.
The first time I did this, I forgot I even had Prime, so I was ready to pay for that for 3-5 day shipping. What a pleasant surprise that was!