Because all of the feeders did not consent to the same thing.  They act competitively and the market power people do not.  There is a difference in economic power here. 

There are two golden rules:

1)  Do unto others as you would have them do unto you.

2)  The one who has the most gold rules.

Our country's laws are premised on protecting everyone from 2).   Number one is infinitely more devine and just.