Amazon already gives a discount if you're willing to wait for them to batch deliveries. Personally I would still have an order arriving every other day regardless of walkable/bikeable infrastructure. Same as most Americans.
Do most American's have an Amazon delivery every other day? It's not what it feels like where I live, but I might live in a part of the country unusually avoiding Amazon. While I see an Amazon truck every day, they visit 1-2 houses around me out of hundreds.
If feels like there are Amazon households that get a delivery every or every other day and non-Amazon households that order 1-5 times a year (if that) and batch their purchases from other retailers (physical or online). That's the genius of Amazon. Those that use them, use them a lot.
"most americans" absolutely do not have "an order arriving every other day".
I order amazon on average once every 3 weeks. My mother (who has full time career and is under 60 years old) has never used amazon. Other members of my family also seem to rarely use amazon.
Also, having an order arriving every other day is incredibly wasteful.