Yes, but wasn't one of the primary purposes to prevent states from interfering with interstate commerce?
Yes, but you're speaking of a probable motive of the law suits, and not the suits themselves. If you grant someone's motive is sufficient grounds, where do you stop? If all I need to do to enact a law is claim that someone wants to interfere with interstate commerce, then I can enact almost any law. It doesn't matter that we agree about the motive in this case.