$10 at mcdonalds gets you 1 meal.
for that price, you can buy some tomatoes, cucumber, a loaf of bread, sandwich meat, juice concentrate, and eat for several days.
healthy food is not more expensive, it's that shitty food is quick and tasty. people are too lazy to make a meal so they go buy one. and what do you typically buy? something that tastes good. grease tastes good. salt tastes good. sugar tastes good. this is also shit that will kill you. but anything to spare having to walk your lazy ass to the grocery store and prepare something for minimal cost.
oh, another big problem with health is the desire for instant gratification. i feel hungry and i want to feel full, so what do you get? shit that tastes good and makes you feel full. carbs fill you up. eat some waffles, eat some crackers. shit also makes you fat if you dont burn it. so people who stuff their faces with that shit at night just pack it, and after a few years, bam, you're a roley poley motherfucker. who eats carrots and bananas and shit at night? hardly anybody. but that shit is low in carbs and good for you. not to mention inexpensive. but, it isn't tasty and doesnt really "hit the spot" like many of the fatty / high carb foods.
any way, if you're looking for prime rib, yeah there are delicacies we can do without. but as a whole, it's way cheaper to eat well. shop in bulk, buy fruits and veges, proteins, grains. none of it is expensive, really. certainly not in comparison to the other shit people tend to chow down on. so it's cheaper and healthies, but not "easy" and "tasty". why cook when you can pay for something that's already prepared, why eat something that's ok when you can eat something delicious. a philosophy that is slowly destroying us. and by "us" i mean you fat american fucks (dont get mad bro, im just being deliberately controversial).