The video shows an altercation between Costco employee Tison, and Garrett, a customer. Garrett can be seen holding his camera phone up to Tison, saying, "I'll just put you on my 3,000-follower Instagram feed."
In response, Tison looked directly at the camera and said, "Hi everyone, I work for Costco and I'm asking this customer to put on a mask because that is our company policy."
Garrett was quick to respond.
"And I'm not doing it because I woke up in a free country," he said.
The Costco employee can then be seen grabbing the customer's cart and walking away with it.
Garrett also posted a selfie-style video to Reddit after the incident, which he later deleted, defending his decision to not wear a mask and referring to those who did as "sheep."
Garrett told Storyful that he has been isolating at home for the past two months and does not have COVID-19. He said that he believes requiring everyone to wear masks is unjust.
"We should be moving forward as a country," he said.
A Twitter user who identified himself as the Costco employee in the video said, "People of Twitter, thank you for all of the support. I was just trying to protect our employees and our members."