But some of the chains say that so far, the menu changes have been a lot of trouble with little reward. Customers apparently just don’t think a value meal pairs well with a cabernet, and the logistics involved with selling alcohol can be daunting and expensive. The problems include obtaining permits, training a staff that has high turnover, slowing down service when IDs have to be checked, and finding a dedicated area for alcohol service.

Image Credit... Matthew Ryan Williams for The New York Times

“Fast-food restaurants aren’t set up to be bars,” said David Henkes, who advises restaurants on alcohol sales at the consulting firm Technomic. “Based upon the amount of sales that most restaurants would get from alcohol, it’s just not feasible for most restaurants to do it.”

With so many employees under the legal drinking age of 21, fast-food restaurants have a particularly hard time when it comes to alcohol service, said James M. Seff, a lawyer who advises wineries and breweries at Pillsbury Winthrop Shaw Pittman.

“If someone is 18 and a buddy comes in who’s 18, chances are better than otherwise that the minor will serve them,” he said. “The regulatory authorities will murder them if there is a pattern in practice of service to minors.”