Unless we want to make people accountable for running their own sophisticated clinical studies for every single product we buy, we should probably have some rules in place around false claims and false advertising.
Maybe we should also have some rules around false claims and false advertising around food in general. I think this causes more damage than homeopathic stuff ever can do.
At the end of the day, people are allowed to buy dumb shit. 50% of my local CVS is make-up, which is way more egregious than echinacea root extract.