To the extent that there's some sort of clinical statistically significant lift over, say, however you might control for a placebo here, who knows? To the extent that it's working for you in a meaningful way, placebo or not... does it even matter? If they're working for you, they're tautologically not a scam, except insofar as you find yourself missing out on benefits promised that aren't being realized, or you feel that the price you've paid is disproportionate to the benefit because some much cheaper option exists in some sense.

Put another way, placebo or not, if there's an effect, and it's a positive one for you, it really doesn't matter. It's working.