Something being "supported by market conditions" is not a valid test for reasonableness. During disasters for example, all manner of unethical practices can be "supported by market conditions". Yet we enact laws against those things for good reason.

You also seem to forget the fact that much of those market conditions are a result of anti-competitive and anti-consumer laws guaranteeing their the status a middle men by force.

If for example consumers were able to buy directly from manufacturers but chose to pay more at a dealership because they thought the extra cost was worth some surplus value provided then you might have a point.