It has become more expensive to eat out over the past five years, with food away from home increasing by 30 percent, according to the Bureau of Labor Statistics. In just the past year, the cost of eating at a fast-food restaurant has increased by more than that of a full-service restaurant.

Within the consumer price index, the limited-service meals category (food that is ordered at a counter and taken to go) rose by 4.3 percent year over year in July. By comparison, full-service meals (sit-down restaurants with wait staff) increased by 3.8 percent over the same period.

Mcdonald's was recently stung by reports that it was charging $18 for a Big Mac, prompting the company's president to issue an open letter in May.

"I can tell you that it frustrates and worries me, and many of our franchisees, when I hear about an $18 Big Mac meal being sold—even if it was at one location in the U.S. out of more than 13,700," McDonald's USA President Joe Erlinger wrote, noting that the average price of a Big Mac across all U.S. franchises had gone up by 21 percent since 2019, from $4.39 to $5.29 today. 

According to a McDonald's "myths vs. facts" sheet, the company increased average menu prices by about 40 percent over the past five years, which is in line with the increase in the firm's costs. Employee salaries have gone up by 40 percent since 2019, and food and paper costs went up by 35 percent during the same period, the company stated. 

At some point, however, customers will question the value of fast food, compared to alternatives such as full-service restaurants or eating at home, industry experts say. 

"People like going to Subway to grab lunch. It's cheap, it's quick, it's easy, it's good. But they question whether they want to pay $12.99, or $14.99, for what used to be an $8.99 bundled meal," Gary Pryor, a former owner of restaurants and food production companies and a business consultant at Waters Business Consulting Group, told The Epoch Times.