The so-called Museum Store, which will open to the public on Wednesday, sells everything from t-shirts to bracelets.
Though other significant memorials, like the Holocaust Museum and Pearl Harbor Memorial, have shops, the Museum Store has drawn the ire of those who believe it capitalizes on the tragedy.
"I honestly don't think it's appropriate -- selling scarves to commercialize the deaths of 3,000 people," Brooklyn state Sen. Martin Golden told the New York Post on Monday. "I don't think it is right."
"I think it's a revenue-generating tourist attraction," Jim Riches, a retired firefighter who lost his son on 9/11, told CNN. "Basically, they're making money off of my son's dead body. I think that's disgusting."
Others see the gift shop as an opportunity to remember lives lost and to contribute financially to the museum.
"It's not a gift shop on a grave site. It's terrible to depict it that way," retired firefighter Ron Parker told CBS New York. "It's a bookstore with a great many heroes. There's a great many stories about a great many heroes in that bookstore."
Michael Frazier, the museum's senior vice president of communications, said in a statement that as a non-profit organization, the memorial "relies on private fundraising, gracious donations and revenue from ticketing and carefully selected keepsake items for retail."