For those in the $75,000-and-above category, 51 percent said they hit a fast-food restaurant at least weekly, while only 39 percent of those earning under $20,000 a year do so, Gallup's annual consumption poll found.
The poll, conducted July 10-14, found 8-of-10 Americans reported eating at fast-food at least monthly, while only 4 percent said they never dine at fast-food restaurants.
The survey also found more than 7-in-10 who ate fast-food weekly or more frequently said it was not "good for you," but 19 percent of those who ate fast-food once or twice a month said it is fairly or very "good for you."
Twenty-eight percent said the food was "not good at all for you," 20 percent said they believe food purchased at fast-food restaurants was "fairly good for you," while 2 percent said it was "very good for you."
Young adults ages 18-29 ate fast-food most often, with 57 percent said they do so at least weekly. Fast-food consumption declined with age; the percentage who said they ate fast-food at least weekly dropped to 41 percent among those age 65 and older.
Fifty-three percent of Hispanics and 52 percent of African-Americans said they ate fast-food at least weekly, while 46 percent of whites said the same.
The telephone survey of 2,027 adults has a margin of error of 3 percentage points.