This guys reasoning is flawed. Shops don't hire fewer people when the minimum goes up, at least not for long. They merely raise prices, causing other shops to raise prices and eventually the 10 bucks an hour will buy less than the 5 bucks did before the government forced private enterprise to pay what the government wants them to pay instead of what they could afford to pay.
Minimum wage laws are evil and counter productive.
No, his reasoning is sound.
Consumers will not pay 10 bucks for a 3 dollar hamburger.
He might as well raise the price to a million bucks on the principle that he only has to sell one to make it.
Price is limited by demand.