Digital coins are usually created to make transactions easier. Crypto coins make it easier to purchase other crypto coins than to convert US dollars to crypto so makes sense to create digital coins linked to the dollar. Using US dollars to make purchases of AMZN products is NOT difficult so what purpose would there be to create AMZN coins (linked to the US dollar) to purchase AMZN products?
Well from a business perspective... 10 years ago they would have been selling toasters for about 1.5 btc. So that would have worked out well for them.
So you're suggesting they link the AMZN coins to BTC? I think people that purchase BTC would rather use BTC for investing/trading rather than make purchases, at least until the US dollar completely falls apart.