If by "legitimate" you mean "useful" or "good" (as opposed to the law not being passed through the established legislative process, because that criticism would

If by "legitimate" you mean "useful" or "good" (as opposed to the law not being passed through the established legislative process, because that criticism wouldn't make sense), then even then it was illegitimate. If the manufacturer can come in and undercut the dealer, they should. Unfortunately, the dealer was local and the manufacturer often wasn't. The same reason any protectionist measures are created.