How much is the right amount for a bowl of noodles? Why can't the price of some breakfast restaurants go down when it goes up, and I ate a bowl of shredded pork noodles for 15 yuan this morning, and I remember when pork was 30 yuan a pound two years ago

I remember that in the first two years, when pork was 30 yuan a pound, shredded pork noodles were 15 yuan a bowl, and meat buns cost five cents a piece, and now when pork falls to 10 yuan a pound, shredded pork noodles are still 15 yuan a bowl, and I wonder if they used to sell at a loss, or now they make too much money?