When a food critic comes to a city that is proud of its dining scene, restaurants and their devotees take notice. But rarely does a traditional reviewer cause as much excitement as Atlanta has seen with the recent visit of Keith Lee, a food obsessive with a vast army of 14 million followers on TikTok.

Mr. Lee, known for his ability to revive a small business with his legions of fans, was often frustrated with what he believed to be odd rules at different restaurants.

“Butter’s a dollar? At a breakfast place?” he asked in a video on his first day in Atlanta, eating takeout in his car. Mr. Lee, who is based in Las Vegas, mostly reviews independent, mom-and-pop restaurants, many of them Black-owned. He often orders takeout and has his family pick it up, so he does not receive star influencer treatment.