When it comes to late-night comedy shows, President Obama is a prolific guest, but taxpayers might not be laughing along with him.

Mr. Obama’s televised chat Tuesday on “The Tonight Show” with Jay Leno in Los Angeles was his 10th appearance on a TV talk show while in office, outpacing all other presidents and hosts since the days of John F. Kennedy and Jack Paar in the early 1960s.

The goal of these appearances is partly to boost the president’s image and partly to promote his agenda. Taxpayers foot the bill for Mr. Obama’s high-cost travel on Air Force One.

At $180,000 per flight hour to operate the presidential aircraft, the trip cost taxpayers more than $1.8 million just for the flying time to California and back. That doesn’t include two 50-minute flights in California on Marine One, the presidential helicopter; or the cost of lodging dozens of White House staffers and Secret Service agents overnight, or the cost of 20-vehicle motorcades at the various stops.

As usual, the White House mixed business with talk show pleasure during the two-day presidential trip. On his way to Los Angeles, Mr. Obama stopped in Phoenix to deliver a speech about the housing industry. He also spoke to Marines at Camp Pendleton in California before flying back to Washington.

The president also made time in Los Angeles for a private dinner Tuesday night with mega-fundraiser Jeffrey Katzenberg, CEO of the DreamWorks Animation film studio, who raised and donated nearly $10 million for Mr. Obama’s re-election effort last year.