Steven, there is a difference between selling your product at whatever price you desire, and requiring that secondary sellers charge for your product. It is also known as Price fixing, and is generally one of the items brought up during anti trust cases.
I do agree, that they are legally allowed to charge whatever they want and they don't have to sell to people who are not willing to follow their price requirements.
I don't know the actual prices, but let's say they sell the ball to a proshop for $140, if that pro shop only wants to make $10 on the ball, shouldn't they be allowed to sell the ball for $150? The supplier already got their money, what should they care?
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