Amazon owns the relationship
You get the sale, they get the customer, the data and the repeat purchase. For a brand trying to build direct revenue, that is the whole trade-off.
Google sends them to you
The visit lands on your store, your email list, your remarketing pool, your data. More work, more margin, more control.
The economics
Amazon fees plus advertising costs frequently exceed a well-run Google account’s cost per order. The comparison people make — CPC versus commission — misses that.
Where Amazon wins
Categories where buyers search there first and price-compare on delivery speed. For those, being absent is a decision too.