Ironically, Amazon doesn't have a way to figure out what price is appropriate ahead of time without consulting a broader market. They face a similar problem as

Ironically, Amazon doesn't have a way to figure out what price is appropriate ahead of time without consulting a broader market. They face a similar problem as central planners - they don't know what the market price for anything is. They could run their website as a big real time auction house, but that'd be a touch unsettling for customers because prices would be continuously fluctuating. It is probably better if they use scraping to short-circuit that process. I wouldn't describe it as unethical. The problem with collusion is more about what happens to companies that undercut the market by a little bit. As long as there are no non-market consequences the incentives should play out as expected. It isn't a problem (indeed, in theory it is expected) that merchants all offer the same good/service for the same price.