i don't understand it because surely they could just give you a reasonable amount of food without markedly affecting their profit margins? do they really think they'll maintain a customer base when they serve a fifth of a meal?

pizzerias over here have it figured out: sure you can charge a lot if that's what it takes to survive as a business, but then you also make sure to give people like 1.5 meals worth of food, then it actually feels worth it and people won't chafe at the idea of giving you patronage.