McD's has better standards than the other FF choices, I think, they probably get evaluated more often. When I was a kid, the gas station bathrooms were horrible, and one reason McD's caught on was simply having clean restrooms. Gas station franchises just had very little if any oversight from "corporate".
We had breakfast at a McD's on our recent short trip, it was quite pricey. $16 or so as I recall for two. We used to go in Cincy to a McDs for breakfast once a week or so, and it was closer to $6-7. We all know everything is up, probably more overall than the reported CPI.
The tavern next to us had "totchos" for $10 preCOVID, now they are $15. The owner told me his potato costs had gone through the roof. Here the food comes from "Sysco" et al., which is a reason I think food in France is overall much better. I hate seeing Starbucks in Paris though. It's amazing how much our "culture" has traveled the world.