Chris Martin "tips in concert tickets".
The Coldplay frontman was one of a number of famous faces Years & Years bassist Mikey Goldsworthy served while working as a waiter at upmarket London restaurant the River Café, and he admits the celebrity diners all tipped at varying rates and he "reluctantly" went to see the 'Paradise' hitmakers perform after being rewarded for giving good service to the singer.
Mikey told Q magazine: "Bono was really good. I can't say how much but he was very generous.
"Paul McCartney was not the best tipper, but it meant more. Hes old school so he came and gave it to you personally.
"Chris Martin tipped in concert tickets. Did I want to go? Will, I went reluctantly all the way to Wembley."
Working in the restaurant and getting so close to the diners meant Mikey often came home with lots of gossip from overheard conversations.
He said: "Victoria Beckham was [there] with David and Gordon Ramsay and I think Gordon paid.
"They were going to start a restaurant but it fell through."
His bandmate Olly Alexander exclaimed: "You have the best goss!"
Bono isn't the only "really good" celebrity tipper.
It was previously revealed Calvin Harris left a $1,000 tip to the captain and crew of a yacht he rented for six hours after filming his video for 'How Deep Is Your Love' starring Gigi Hadid on board.
Last August, Kim Kardashian West gave $300 after lunch with friends at Brennan's in New Orleans, in recognition of the service they received for their $200 meal.
Amy Schumer left a $500 tip for a student working at Peter's Clam Bar in Long Island, New York, despite her bill only coming to $49.
The 'Trainwreck' star reportedly opted to leave the generous sum after an "engaging, animated conversation with her server, Ryan".
During the course of their conversation, Ryan explained that he was "a college student working two jobs to fund his education" and so Amy decided to be particularly kind when it came to paying the bill.
And last March, Charlie Sheen left a $1,400 tip on a $629 restaurant bill.
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