Profit margin is phenominal! Cost them $0.50 to $1.00 to make, box and $2.00 each to market, and you sell them with a killer bottom line!
Like Slick 50, another snake oil, does nothing (Feds sued and won) and they still are in business. People are still convinced on the hype.
Like Split Fire plugs. Same deal. I would bet anyone that if you give me 6 alternating dyno runs (3 brand new AC Delco factory spec plugs) vs 3 Split Fires on a dyno, you will see a variation that sits well within the margin of error on the dyno, not enough to warrant the cost of the efforts.