Remember the $0.39 menu at Taco Bell? That was still there in the 90’s if you wanted supreme it was .49 and .59 now even a soft taco is like $2 something.
I had a classmate in high school that worked at the local taco bell, and if we went in late, could order a burrito or two, and for under $1.50, have more overstuffed burrito than we cared to eat.
Taco bell is still one of the value leaders if you choose wisely (and if you like taco bell, lol). They have the craver-whatever-it-is combo for $6 or another for $9, provide a filling amount of food including the side and drink.
Cheapest way to get a lot of protein to just hold you over till the next meal, I'd still pick 2 x McDoubles at $2.50 a piece, for $5 total. I wouldn't enjoy them but if hot, and enough ketchup, they'd go down and I'd be good for a few hours.
It all makes me think more about prior planning... I mean I fix a lot more food with leftovers and just have to plan ahead and don't need fast food. If it's going to cost > $10, I could just freeze something and if I get it out in the morning and put in an insulated cooler, it's still safe to eat by lunch.
Right now I'm eating a leftover slice of pizza that I froze, and it thawed, and it hits the spot. Cost < $1. Granted that cost per slice is because it was a Kroger's rising crust frozen pizza, that I substantially improved with more toppings, my own sauce added from home grown tomatoes, etc... it's a system (or a madness, lol) incorporating some amount of ready made food with what you add, to end up with an acceptable, palatable outcome. I'm easy though, hot sauce fixes
most things.