That was my thought about the statistic that Americans eat 3 burgers/week - they have no idea how many people are eating homemade burgers, they're only basing it on fast food burger numbers.

Or if they're basing it on how much ground beef is sold and assuming people only buy ground beef to make burgers at home - well, that's rather presumptuous of them, isn't it? People make spaghetti, stuffed peppers, chili, tacos, meatloaf, manwich, lasagna, all kinds of hamburger helper, just to name a few other things you can make from ground beef. There used to be cookbooks with titles like "100 ground beef recipes".

You're right that it's highly unlikely McD's (or any other burger joints) will offer a plant based cheese option on their burgers. They're not even offering gluten-free options - specialty diet options which only appeal to a tiny percentage of their customer base just doesn't work well with the fast food business model.

Do any fast food places still offer meatless burgers? I never hear about them having meatless burgers on the menu any more.