I’m shocked by one aspect of the story of the guy selling $30 hot dogs to tourists near the World Trade Center — shocked that he was fired. Who knew hot-dog men could be fired?

As for that other detail — selling a hot dog for considerably “more than it’s worth,” so what? Apple makes a huge profit on every device it sells. Does anyone think Apple is guilty of “price gouging”? Moreover, a hot dog is guaranteed not to shatter when it falls on the sidewalk, and I’ve never had to reboot my sauerkraut. No hot dog has ever been rendered obsolete by a new model that has a slightly thinner bun.

Hot-dog guy Ahmed Mohammed — let’s be accurate and call him Hot Dog Hero — was simply exercising his right to sell stuff in the marketplace for whatever he can get for it. Why begrudge him a large markup if he took advantage of the fact that some people are stupid? Taking advantage of stupidity is an important driver of the economic engine. Without taking advantage of stupid people, how would haute-couture designers sell a couple yards of shiny fabric for $2,000? Without taking advantage of stupid people, how would the New York State Lottery rake in $3 billion in profit? Without taking advantage of stupid people, how would the Franklin Mint have sold off millions of dollars worth of plastic copies of Jackie Onassis’ plastic pearls? If the stupidity were ever wrung out of the system, our economy would be the size of Bangladesh’s.

All of these stupid people are exactly what Hot Dog Hero’s “victims” were — willing customers. There was no coercion. No one was being lied to. What your mother said when you were talked into doing something dumb still applies: “Did anyone hold a gun to your head?” At worst, HDH was guilty of a little nontransparency, but if that policy were consistently enforced the courts would be overloaded with restaurant operators who don’t publish their cocktail prices on the menu.

A good or service doesn’t have a fixed worth — the value can vary wildly depending on the circumstances. This is why Uber charges $10 for some cab rides, but considerably more when it’s 11:30 on New Year’s Eve in a blizzard. People complaining about Uber’s “gouging” don’t understand that the option to purchase a service at market price is better than not having that option because the service is simply unavailable. People don’t want to climb out of bed and drive you anywhere in a blizzard for 10 bucks.

Is a hot dog ever “worth” $30? Anything is “worth” whatever someone else is willing to pay for it. Anyone who didn’t like Hot Dog Hero’s price could have said, “Get the frank out of here” and handed over $3 — or handed back the wiener and walked away. Wouldn’t that be easier than filing a complaint? If you did file a complaint, you should probably send it to your home address: “Self, we need to have a talk about what constitutes a reasonable price for a hot dog.”

Sorry, tourists, if you feel you were “ripped off.” Let’s look at what you got for your $30. You got a) a tasty snack; b) enough bacteria to inoculate you against any number of diseases; c) a stellar anecdote about American capitalist depravity to take back to Düsseldorf or Lyon; d) a useful lesson that there’s a sucker born every minute — such as the minute listed on your birth certificate.