It’s that time of year again: Girl Scout cookie season. But some cookie monsters won’t be able to get their favorites. The Dulce De Leche and the Thank U Berry Munch cookies are being pulled from the menu in various cities across the country, according to Michelle Tompkins, spokeswoman for Girl Scouts of the USA.

The group’s most popular cookies — Thin Mints, Samoas, Tagalongs, Do-si-Dos, Trefoils and Lemon Chalet Cremes — will still be available everywhere.

The great cookie massacre is happening as part of a pilot program in 12 regions to cut down the cookie menu. Girl Scout councils don’t want to have to deal with a surplus of less popular cookies.

The areas that will be going without include parts of New York City, Atlanta, Oklahoma, California’s Central Coast and Virginia’s Chesapeake Bay region.

The cookie program of Girl Scouts of the USA started as a home kitchen endeavor in 1917. The first commercial sale came nearly two decades later, in 1935.

It’s grown into a big and iconic moneyspinner. In 2010, the program sold nearly 200 million boxes of cookies and brought in $714 million in business for the girls’ troupes.

Currently, Girl Scout cookies are made by two bakeries, ABC Bakers and Little Brownie Bakers. The pilot program is being tested out by the latter, while the former will keep cooking up the full cookie line-up.

The cutbacks are not a function of the down economy, Tompkins said.

“The decision to make the fewer cookies is not based on the economy,“ she said. “It was a business decision made a couple years ago.“

The rationale? Some cookies are just more popular than others.

“Sometimes the market loves them, like the Lemon Chalet, and sometimes they are not as successful,“ Tompkins said. “It is a way of improving business.“

But some trends are eternal: Thin Mints remain the bestseller, and will be on the menu for as long as Girl Scouts are out there selling cookies.