> It's not anticompetitive because they aren't restricting competition off their platform.
Yes, they are. They are using their influence and market power to prevent others from competing on price, using the threat of economic retribution on their platform. If this isn't anti-competitive, then nothing short of sending assassins on your competitors is.
Nonsense. They are only able to influence your behavior if you use them. It is completely self selected.
It is the exact same thing as is argued by social media companies: they have the right to moderate the content posted on their platforms because it's their platforms. You can do whatever you want on your own site.
> They are only able to influence your behavior if you use them.
Yes, companies cannot influence behavior of people or businesses that have no business relationship with them, direct or indirect. In other words, you are saying that indeed, the only anti-competitive action is sending armed thugs to sabotage your competition. Everything else, every contractual condition, is fair game.
> the only anti-competitive action is sending armed thugs to sabotage your competition
I'm saying that entering a voluntary transaction knowing the terms of the trade does not amount to anti-competitive behavior. Nobody forced you into the trade. Nobody prohibited you from entering the trade.
Entering the trade with clear conditions is voluntary. You could easily just not do business with that partner. Here that would be not using Amazon's marketplace.
Yes, they are. They are using their influence and market power to prevent others from competing on price, using the threat of economic retribution on their platform. If this isn't anti-competitive, then nothing short of sending assassins on your competitors is.