The senior citizen was captured working hard outside the fast-food restaurant in Connecticut as younger colleagues stayed inside.
The video, posted by @kanykaine22, has now had more than 2.2m views.
And when she setup a GoFundMe for the worker, who gave his name as Gregorio, she raised more than $40,000 to help him retire.
“I’m at the McDonald’s in Bloomfield, Connecticut,” she says on the video.
“A young man took my order and my payment. A young woman served my food.
“Another young woman came outside to serve people that were doing pickup. I go to my car, and I see this man, outside, in this weather, sweeping this parking, while these three inside, in the AC.
“This man has no water, no food, no one is out here watching him. He’s obviously elderly; he’s at least 70 years old.
“He can’t stand up straight. He’s struggling. You’re telling me people can’t have consideration and help this man? He deserves a f***ing raise; he deserves a gold medal.”
She then sat down with Gregorio and a relative and he thanked people in Spanish for their support.
Social media users were quick to rally around Gregario, who @kanykaine22 said lost his wife to Covid-19 last year.
“This is the world that we live in where elderly ppl like him have to work bc they probably don’t make enough from retirement to survive,” wrote @heyluve_its_nique.
And @savannascholten, wrote: “He should be inside, not out in the heat like that; that is just wrong on so many levels.”