Well, be surprised no more, because that's exactly where the exotic fruit appears.
Organisers have said the move to ban the fuit was because fans of Oxford band Glass Animals bring hundreds of pineapples to their gigs, in a nod to song Pork Soda which includes the lyrics "pineapples are in my head".
Here's what we mean:
Glass Animal's drummer Joe Seaward said it would be a "challenge" to get in with pineapples.
"Anyone who wasn't bringing a pineapple definitely is now," he said.
"It's fruitist. Watermelons are fine, but not pineapples?"
And even though you might not be able to bring in the physical fruit, there are still ways to get around the ban. Just ask these two...
Reading & Leeds Festivals will take place on 25-27 August 2017. Find out more about each festivals on our guides, and book your tickets and packages to each festival here.
More like this: