The dinner with Obama took place on Tuesday at Arthur Bryant's, a popular BBQ joint, during the president's trip to Kansas City.
"I want to pay for everybody," he told the woman at the register counter, referring to the four guests.
The four -- identified as Victor Fugate, Valerie McCaw, Mark Turner, Becky Forrest -- had written letters to Obama about their personal stories of success and struggle of working hard to get ahead in America.
White House Press Secretary, Josh Earnest, who hails from the Kansas City, had called the four and invited them for dinner with Obama.
In January 2012 Victor Fugate wrote to Obama thanking him for the student loan help he received from the Income Based Repayment Plan. Currently, he works for the Missouri Department of Mental Health.
Valerie McCaw wrote an email to Obama last week to voice her frustration about how hard it is to make a living.
As a single mom and a small business owner, she works seven days a week and still struggles to pay her bills. A small business owner and engineer, she started her firm, VSM Engineering, 11 years ago and has four part-time employees, the letter said.
Her son is in college out of state and his tuition is almost USD 40,000 a year.
In June, Mark Turner wrote to Obama about teaching a GED program and trying to make a difference in the lives of young people.
Mark works for the Full Employment Council, a non-profit that helps those who are unemployed and under employed.
Becky Forrest wrote to Obama in August 2013 about the work that was being done through her neighbourhood association, the White House said.
After ordering, Obama headed into another room with black-and-white photos of baseball players lining the walls, where he greeted smiling diners.
The White House every day receives hundreds of letter.
A separate dedicated cell in the White House selects 10 letters every day for Obama to read, which he responds to.
This is probably for the first time that the President has had dinner with those who wrote to him.
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