Quality and size. On a whim I got a fish fillet from McDonalds the other day. At first I thought they gave me a happy meal fish fillet and then I remembered that they don't have that. It was comically smaller than it used to be.
Unfortunately the fish fillet has always been more expensive than other meals. It doesn't surprise me that they made it smaller (I assume to price it the same as other sandwiches?).
Fast food has been so ratfucked over the past few years that it wouldn't be worth it if they hadn't increased prices by 30%+ to match a sit-down restaurant's. When you get a fraction of the food and it's worse, a fast food restaurant adds nothing. Even the convenience is meaningless now that I can order online from most places and it's ready by the time I get there.
Where I live fast food and a large chunk of sit-down food is the same price, excluding tip. I just order takeout now. Saves money and I always have leftovers.
Actually, yes. Part of the reason that fast food was so inexpensive was that fast food workers were criminally underpaid. Wages are up because of a combination of a tighter labor market and improved minimum wage laws. I've always been in favor of this, but in talking to restaurant owners I understood that they would have to pass increased labor costs on to their customers.
Continuing supply chain disruption from COVID-19 seem to also be a contributing factor, but I'm not sure what a recovery there will look like.