You make a good point. However I still think it's underhanded an unnecessary. People are going to buy from amazon for a host of other reasons such as convenience and maybe free shipping if they are prime members. I think amazon needs to compete based on value add, not with an underhanded contract.

I will almost never sign a so-called "standard" software development contract because standard practice is to treat the little guy poorly. I think the same goes with amazon. Just because it is standard doesn't mean it's right.