You're assuming McDonald's has a much higher profit margin than it actually does - it's a restaurant chain, not a software company. In other words, the wages for the guy making the burger isn't the only input to cost. E.g., if the beef in that $2 burger used to cost $0.50, it might cost $0.75 now, partly as a response to the need for the farmer to pay himself more. There's also the people working at the meat processing plant, everything that went into the bun, the transportation costs, marketing costs, etc.