I don't know the history exactly but I think it's been kind of rocky. Amazon limits CCC to physical (that is, Amazon's lowest margin) goods, ostensibly because of licensing agreements.

Amazon benefits here by sanctioning a price history tool with restrictions when others could take its place and include its higher margin goods (if you look, there are CCC competitors that aren't sanctioned in this way, but you have to look). Less measurably, the price history tracker provides better consumer experience, in line with Amazon's customer obsession. And finally, Amazon's warehouse space isn't unlimited, so informed consumers who know a particular price is extraordinary may help it free up space more quickly.