It's not just kids who rack up thousands of pounds playing mobile games. Adults do it, too.
And some of those adults are celebrities.
In a recent interview with The Telegraph, former Sex Pistol frontman John 'Rotten' Lydon admitted splashing out £10,000 - £10,000! - on games for his iPad over a two year period.
Which games? Game of Thrones Ascent, Game of War, which recently hit the headlines for its $40m advertising campaign featuring supermodel Kate Upton - and EA's Real Racing. All three are free-to-play with in-app purchases.
Have you made any extravagant purchases? The Daily Telegraph asked Lydon.
"I wasted - you're the first to know this - 10,000 f‑‑‑‑‑‑ pounds in the last two years on apps on my iPad," he replied.
"I got into Game of Thrones, Game of War, Real Racing, and I just wanted to up the ante. And like an idiot I didn't check myself. I've been checked now. But there's a kid in me, see? A bit of my childhood was taken from me and I'm determined to bring it back."
Lydon, currently promoting his new book Anger Is an Energy: My Life Uncensored, normally plays it safe with his cash, he said, so his iPad game extravagance is a bit out of character.
But while the punk rocker has plenty of money now - thanks to those Country Life butter ads - to afford such extravagance, he's not super duper rich. Which is fine, he says, because he's got a PlayStation.
"There was a time when record companies weren't backing me and I had to lease and flog a few things to survive," he revealed. "None of it's made what I'd call huge amounts of money but it's enough for me to do what I want.
"I'm not a bloke who wants a Ferrari in the garage. If I want to drive a Ferrari I've got PlayStation."
Maybe Lydon could ask Apple for a refund? Claim some kid nicked his iPad or something?