One of the nicer branches of McDonalds is the one opposite Liverpool's Albert Dock. It was one of the first in the UK to try and go for an ambiance that didn't rely on wipe-clean, primary colours and even attempted to make a nod to its surroundings, albeit in the most kneejerk, 'here are pictures of The Beatles because this is Liverpool' fashion.
Oh... hang on a moment: McDonalds. Beatles. Isn't one of the Beatles a bit anti-meat? There's going to be trouble:
"What sort of morons do MCDonald's think Beatles fans are?
"It's ridiculous and insulting to use images to peddle hamburgers. Fans should boycott McDonald's - and not just in Liverpool."
So... McCartney wants people to boycott McDonalds not because they serve beefburgers, but because one of the hundreds of thousands of branches has a photograph of him on the wall?
McCartney doesn't think that Beatles fans are morons, and yet he seems convinced they'll see a black and white photo of him and his band from the 1960s and somehow think that this is an endorsement from McCartney. Curious.