There’s no free lunch – or breakfast or dinner – for President Barack Obama on Thanksgiving Day. Or any other day, for that matter.

He has to dig into his own pocket to pay for his holiday feast of turkey, ham, two kinds of stuffing, sweet and regular potatoes and six different kinds of pie. It’s a longstanding practice that a president pays for meals for himself, his family and personal guests.

Obama also pays for other basics – everything from toothpaste to dry cleaning.

That is a nice sweater. Photograph: Pablo Martinez Monsivais/AP Photo

Why is that?

Gary Walters, who was chief White House usher for many years, said the payment rule dates back to 1800 when the White House was first occupied by President John Adams and there was no staff. Presidents brought staff with them and paid for everything.

Congress gradually began spending money to maintain an official White House staff to oversee operations and maintenance, but presidents continued to pay for personal expenses.

What it boils down to, Walters said, is that the White House is first and foremost the president’s home.

“All those things that are personal in nature that we all pay for, the first family pays for,” he said.

What is excluded?

White House chefs who prepare the president’s meals are paid by the government.

For the budget year that ended 30 September, Congress gave the White House $19,000 to pay for official receptions and $12.7m to cover operating expenses for the residence, which may include entertainment. The cost of meals for some White House events, including state dinners and receptions, is picked up by the State Department or political parties.

First Lady Michelle Obama shops at Target. What a bargain. Photograph: Charles Dharapak/AP Photo

What else must the first family pay for?

Since presidents and first ladies can’t easily pop into the neighborhood drug store, a White House residence staff member will pick up things like toothpaste and deodorant during shopping runs and keep the bill for Obama.

Another cost is private parties, such as the 50th birthday bash Obama threw earlier this year for first lady Michelle Obama. For private events, presidents pay for food and beverages, use of waiters and servers and setup and cleanup crews. Taxpayers are only supposed to pay for official government functions.

How does it work?

The White House usher’s office prepares a detailed bill and sends a copy to the president and another to the first lady by mid-month. It is itemized to account for all the food and beverages consumed by the first family and personal guests, and includes invoices and receipts for those costs and other services.

Obama then reimburses the government.

“It’s just the tradition that it’s continued on through time that the president will pay for their own food and, I guess, if they needed something for the house that was personal. Toothpaste, cologne or whatever,” said William Bushong, chief historian at the White House Historical Association.

Has anyone ever complained about this?

The practice appeared to catch Nancy Reagan by surprise.

“Nobody had told us that the president and his wife are charged for every meal, as well as for such incidentals as dry cleaning, toothpaste and other toiletries,” she said shortly after she and President Ronald Reagan moved into the White House in January 1981.

Laura Bush knew about it – she’s the daughter-in-law of a president – but was still unprepared for some of the costs after becoming first lady in 2001.

One of the heftier expenses for the American first family? The first lady’s wardrobe, according to Laura Bush. Photograph: Charles Dharapak/AP

“I was amazed by the sheer number of designer clothes that I was expected to buy, like the women before me, to meet the fashion expectations for a first lady,” Mrs Bush wrote in her memoir. “After our first year in the White House, our accountant said to George (W Bush), ‘It costs a lot to be president,’ and he was referring mainly to my clothes.”

She also paid “with our own money” for someone to blow-dry her hair most mornings “just so I could try to avoid a bad hair day.”

What is Obama’s salary?

He gets $400,000 annually, plus a $50,000 allowance to help defray costs associated with carrying out his official duties.

What are some of Obama’s other personal expenses?

Mortgage on a home in Chicago, private-school tuition for his daughters.

What else does he get for free at the White House?

Rent, utilities, transportation, security, medical care.