Contract v Statute
It doesn't matter what Amazon (or any other company) puts in their terms of sale -
Law trumps contract every time,
It does mean you will probably have to resort to the courts if you have a valid complaint, but that's what they're for!
It also raises the possibility that if Amazon (or other company) have been deemed to have breached the specific clause relating to formation of contract, then the entire contract has been breached. Although that one's not a given, you'd have to argue about it.