First, our pricing almost exactly matching S3 is not a secret - it's well understood, and by design.
Second, you'll note that the following features of a 10TB account with us are not included with S3:
- Free integration engineering (as in, a unix engineer on the phone with you)
- 24/7 hotline support - as in, xmas morning phonecalls
- two physical media shipments of any size per year
- We will sign a BAA with you
Ask your contact at Amazon what those would cost next time you talk to them. Oh wait, you've never ever talked to anyone at Amazon and you never will[1]
So you're right - it's not apples to apples.
[1] Except, of course, at AWS summit and so on, where they are very available and helpful.