The tonic pushers didn't just dream up the concept while cleaning out their grill after a snake barbecue: They got the idea from Chinese immigrants to America in the 1800s, who at the time were using their own version of snake oil. So in other words, the deathly reach of Big Snake Oil was global.
Well, that's what everyone assumed until someone finally got around to testing the original version of the oil, which is still in use in China. The tests showed it to be incredibly high in omega-3 fatty acids, which have anti-inflammatory properties and can help with pain. So when Chinese workers told Americans that their magic snake oil was the bee's knees, they were telling the truth.
"Good for termite tendons, beetle's elbow, and roly-poly dick."
But if that's the case, why was American snake oil so fucking useless? Well, the Chinese version was made from Chinese water snakes, which as the name implies are not easily found on the American continent. American snake-oil producers either used rattlesnakes, which have much lower omega-3 levels, or simply substituted cow fat. So the next time you call someone a snake-oil salesman for trying to sell you a homeopathic herpes remedy, remember that a more accurate insult would be "19th century entrepreneur without access to a wildlife import license."