Tracy Lewis said she had been selling the cookies for the past three years of the 28 years she worked on the campus, most recently at the Eagle's Nest convenience store.
"I had the cookies on a cart, and I would never ask anyone to buy them, " Lewis said. "But, If they wanted to buy some, I would sell them."
In a letter from the Bon Appetit Management Co., her manager accused her of "gross misconduct by soliciting," and "operating a cash business selling Girl Scout cookies over the counter, which violates company policy," WTTG-TV, Washington, reported Friday.
"They didn't give me any warning," Lewis said. "It's crazy because I can't profit for selling the cookies.
"It's a volunteer position. I was just trying to help my daughter raise money for trips and stuff like that."
Colleen Cibula, chief operating officer of the Girl Scouts Council of the Nation's Capitol, released a statement saying parents should think again about selling cookies at their workplace.
"Girl Scout cookie sales are a girl-led, entrepreneurial program. We want the girls to be taking the lead," she said.
2014: The Year in Music [PHOTOS]