It's pretty easy for things to not be actual collusion to end up looking like it, and having the very same negative effects" You don't need handshakes in backrooms.
This will be even more popular in situations like supermarkets, where a significant part of the stock has an expiration date that isn't so far from today. Turning your inventory too fast is just as bad as turning it too slowly, so there can be immediate reactions to make sure things are being consumed at just the right speed. And the more uniform the models of consumption the supermarkets are running, the more similar their decisions will be anyway.
So I wonder if we even need to focus on needing damning evidence, or on whether there is collusion, and instead aim for what we want: Dynamics that put negative pressures on prices. If we aren't seeing that, I don't care much about how much is collusion, and how much is models that have tacit agreements because, as market players optimize for what is best for them, there are solutions where high prices across the board makes all sellers win.
This will be even more popular in situations like supermarkets, where a significant part of the stock has an expiration date that isn't so far from today. Turning your inventory too fast is just as bad as turning it too slowly, so there can be immediate reactions to make sure things are being consumed at just the right speed. And the more uniform the models of consumption the supermarkets are running, the more similar their decisions will be anyway.
So I wonder if we even need to focus on needing damning evidence, or on whether there is collusion, and instead aim for what we want: Dynamics that put negative pressures on prices. If we aren't seeing that, I don't care much about how much is collusion, and how much is models that have tacit agreements because, as market players optimize for what is best for them, there are solutions where high prices across the board makes all sellers win.