>The real problem is that corporations are too big. //
How about if all the workers in Amazon eco-system shared the money equally (according to the retail price index in their locality, perhaps), and reduced the cost of goods to ensure that the per-employee share matched the median societal wage (or something similar)? Still a big fat corp, but not contributing to societal inequality or unfairness (but still a problem for over-use of resources and such); how would that fit with your analysis, would it still be "these corps are too big"?
Of course, because you'd still have a single entity in control of hundreds of billions of dollars in resources. The CEO still has the same amount of money to lobby the government to relax environmental rules or suppress wages or competition or fix prices or whatever problematic thing Abstract Evil Corp does when they're too powerful. They still have the same huge pile of cash to undercut competitors with until there are none left. The size of the company is problematic independent of where the profits go.
It's also somewhat of an implausible hypothetical, because paying significantly above market wages is uncompetitive. If Amazon pays market wages then nobody can undercut them on price because they have better logistics. If they paid significantly above market wages then someone else could pay market wages and undercut them. The only way out of that is to get market wages up and consumer prices down to the level you're talking about -- which is what happens when there are more employers competing for labor and customers.
How about if all the workers in Amazon eco-system shared the money equally (according to the retail price index in their locality, perhaps), and reduced the cost of goods to ensure that the per-employee share matched the median societal wage (or something similar)? Still a big fat corp, but not contributing to societal inequality or unfairness (but still a problem for over-use of resources and such); how would that fit with your analysis, would it still be "these corps are too big"?