Re: "Natural frequencies"??
We don't have to prove that it doesn't work, if challenged, the company pushing the snake oil has to prove their claims. Typically, they'll sell the junk till they get challenged, making a small fortune until the regulators get at them, at which time they'll quietly disappear.
Remember a few years ago those miracle devices that were supposed to treat joing pain, arthritis, etc...? They were nothing more than gas grill ignitors.
Absolutely no medical validity at all, and they sold these $2 devices for $40!
The company went away when they were instructed to document their claims.
The hucksters made millions.
Then there were the magical cattle magnets. Same type of scam. First they somehow allowed cars to get better fuel economy. The magnetism somehow realigned the molecules in the gasoline to allow it to burn more completely or with more power or some other bold faced lie. The FTC made them prove their claims, and of course they couldn't cause it was all hooey.
Then these same hucksters laid low for several years, and pushed their left over inventory as water softeners- claimed the same bs- that the magnetism aligned the water molecule and lo and behold- free soft water!
More hogwash.
The general pattern of a scam is to lie, and sell as much as possible before you get pushed off the air.