Harry Potter has millions of fans. Benjamin F. Bailar is not one of them. The 80-year-old former postmaster general and avid stamp collector sent a letter last month to Patrick Donahoe, the current postmaster general, berating the United States Postal Service for including the boy wizard on its postage stamps.

“The stamp program should celebrate the things that are great about the United States and serve as a medium to communicate those things to a world-wide audience,” Bailar wrote in the letter, which was first reported by Linns Stamp News and The Washington Post. “To prostitute that goal in the pursuit of possibly illusory profits does not make sense to me.”

Bailar expressed frustration that the Citizens’ Advisory Stamp Committee (CSAS) was not consulted about the Harry Potter decision. Bailar, who resigned as a member of the exclusive committee July 23, argues that the post office has “become heavily weighted to artists and designers with fewer and fewer people who can truly provide solid input on the subject matter of stamps.”

“While this may support a drive to ‘sell the product’ with abundance of pretty and popular culture subjects, the result is a program that lacks gravitas,” he added. “Given the apparent desire of USPS to commercialize the stamp program, I would suggest that the committee be eliminated, or at the very least be further marginalized.”

The Harry Potter stamps, based on the best-selling books by J.K. Rowling, debuted in 2013. More than $100 million of these stamps have been sold.

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A USPS spokesperson provided this response to Yahoo Finance:

“The Postal Service will discuss the concerns Mr. Bailar raised in his letter with our CSAC Chair, Janet Klug, and the full CSAC committee. The Postmaster General and CSAC members wholeheartedly agree with Mr. Bailar that the stamp program should celebrate the things that are great about the United States and serve as a medium to communicate those things to a world-wide audience."

The CSAS has been evaluating all stamp proposals since 1957. Committee members are appointed by the postmaster general and meet every quarter to review potential stamp subjects. The committee recommends an average of 25 to 30 subjects each year based on 11 criteria and the postmaster general chooses the winners.

The Postal Service released its new Janis Joplin stamp Friday, the fifth in the Postal Service’s Music Icons series. Over the years U.S. stamps have celebrated cultural American icons such as Harvey Milk, Jimi Hendrix and Charlton Heston and American pastimes such as farmers markets and Hot Rods.

“Maybe it’s a good thing that the post office is doing something the customers want to buy,” says Yahoo Finance’s Aaron Task in the video above.

The Harry Potter brouhaha has become the latest headache for the cash-strapped post office. USPS, which does not receive any tax dollars for operating expenses, relies on the sale of postage, products and services to fund its operations. The Postal Service has been struggling to pay its future retiree health care benefits, which is mandated by law. The Postal Service reported a net loss of $1.9 billion in the second quarter. It owes $99.8 billion in benefits to current and retired workers and another $16.7 billion to future retirees, according to a March 2014 GAO report.

The Postal Service has been teaming up with online retailers like Amazon.com (AMZN) to boost revenue by delivering packages in New York and Los Angeles metro areas on Sunday. A cost-cutting proposal to end Saturday mail delivery was rejected by Congress. The Postal Service also earns money from its private sector competitors FedEx (FDX) and UPS (UPS), who pay USPS to deliver 470 million of their ground packages to residences. First-class mail still accounts for nearly half of the USPS's revenue, reports The Wall Street Journal, and postmaster Donahoe has said he wants to double the Postal Service’s package-delivery business within a few years.

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