It couldn't. When government chemists finally tested it in 1916, there wasn't any snake in it. Just mineral oil and beef fat. He was fined $20.
Stanley wasn't the only one at it, though. Patent medicines were everywhere, and loads of them were just as dodgy. In fact, people were already onto the scams long before Stanley. Collier's Weekly ran an exposé on the whole trade in 1905, and a year later, the US passed the Pure Food and Drug Act.
That law applied to everyone. Every seller had to print what was actually in the bottle, including the alcohol and morphine that plenty of them relied on. Mrs Winslow's Soothing Syrup (sold to calm teething babies) had to take the morphine out and drop "soothing" from its name. Sales fell. And every time sellers found a loophole, the government closed it, first in 1912 and again in 1938.
"Snake oil salesman" has been an insult ever since.
The lesson? If customers don't like something and you're only doing it because everyone else does, someone's going to get caught for it eventually. When they do, you'll go down with them.
So don't do that thing.
The snake oil salesmen never went away
Despite the story and new regulations, we still see companies pushing the limits of what they should do almost daily. Here are just a few recent examples:
A "sense of pride and accomplishment”
In 2017 EA launched Star Wars Battlefront II, a full-price game where you could pay real money for loot boxes (random prizes that helped you win). Players worked out it would take around 40 hours to unlock Darth Vader without paying. EA's reply on Reddit said the idea was to give players "a sense of pride and accomplishment." It got about 668,000 downvotes and a Guinness World Record for the most downvoted comment. EA pulled paid loot boxes a few months later.
But EA wasn't the only one selling them, so the whole industry got the blame. Belgium ruled loot boxes were illegal gambling in 2018. Brazil banned selling them to under-18s in 2026, and a Brazilian court has since ordered Riot Games and ten other companies to pay more than 300 million reais between them (around £45m).
Easy to sign up, hard to leave
In 2025, Amazon paid $2.5bn to settle a US case over how hard it made Prime to cancel. Plenty of subscription businesses make leaving a pain. Amazon just got caught doing it at a very large scale. And if your business relies on people forgetting to cancel, UK rules are coming for that too, probably in spring 2027.
Surprise, surprise, there's another fee
You know the feeling. You pick your tickets, head to checkout, and the price creeps up. Surprise fees like that have been banned in the UK since April 2025. StubHub's already been fined nearly £900,000, and the AA and BSM driving schools were fined £4.2m for the same thing. After the Oasis sale, the CMA also made Ticketmaster promise to show fans the full range of prices before they'd even joined the queue.
You paid for it, but you don't own it
When Ubisoft switched off The Crew in 2024, people who'd paid for the game couldn't play it anymore. That's legal, for now. But it kicked off Stop Killing Games, a campaign that's got 1.29 million verified signatures and is sitting with the European Commission. If that turns into a law, it won't only apply to Ubisoft.
A monthly fee for seats you already own
In 2022, BMW started charging drivers in the UK and a few other countries a monthly fee (about $18) to turn on heated seats that were already fitted in the car. People were furious. BMW dropped it in 2023, and its head of product communications admitted it "was probably not the best way to start." This one never got as far as a regulator. BMW backed down first.
None of these businesses set out to annoy their customers (at least, we hope not). Most of them were doing what everyone else was doing, or they were chasing profits without really thinking about what was best for the end customer (or what people actually wanted).
