Ron Paul (historically, I haven't watched this particular clip) takes it too far, though. While I agree that people should be able to put whatever they damn well please in their bodies, I also think that the government should have the power to prevent a person from selling something as a medicine when there's no proof of its safety or efficacy.
As a recreational drug or even just a tasty treat, go wild, but as soon as you start calling it medicine, you're making medical claims that should be backed up by scientific evidence.
Unfortunately, the FDA has been pretty lax lately on keeping people selling dietary supplements from advertising as if they were selling actual medicine.
I was amazed at the number of medical MJ places in Colorado. Wonder how hard it is to get a doctor's note saying you have anxiety or insomnia?