It was a time when prices weren’t fry-way robbery. Once an oasis where the cash-strapped could eat on the cheap, fast food is rapidly becoming a luxury that people splash out on for special occasions. McDonald’s has been called out for selling a $18 Big Mac combo in Connecticut , while Danny Meyer’s upmarket burger monger Shake Shack was grilled on social media for reportedly charging $50 for two sandwiches and a drink — the price of a sit-down meal in many fast-casual spots. According to the