As a windblown President Trump boarded Air Force One in Mountain View, Calif., earlier this week, a Reuters photographer captured a curious image that showed Trump’s tie over his shoulder and what appeared to be a wad of cash in his back suit pocket.

On Wednesday night, Trump offered an explanation to reporters traveling with him back to Washington: He doesn’t use a wallet because he no longer uses credit cards, but he likes to leave cash tips at hotels.

Amid a wide-ranging question-and-answer session, a reporter noted that Trump had been photographed with his jacket up in the wind and that $20 bills were visible — and asked if he regularly carries cash in his pocket.

“I do! I do!” Trump said, taking a wad of bills out of his pocket and holding it up for reporters to see.

“I don’t carry a wallet, because I haven’t had to use a credit card in a long time,” Trump said. “I do like leaving tips to the hotel. I like to carry a little something. I like to give tips to the hotel. I’m telling you, maybe a president’s not supposed to do it, but I like to leave a tip for the hotel, etcetera, etcetera.”

“Oh, that’s funny. So the jacket was blowing up?” he added, also observing that the press has “good cameras.”