For the price of a fast food value meal today (around $9 - $15), you could afford about 3 healthier meals.
I literally just calculated my brunch costs (1 egg and 1 egg white, oatmeal, peanut butter, beans, broccoli, and berries)
It cost me less than $2 for the entire meal (about 750 calories - average human doesn't even need 3 of these meals to hit their calories for the day).
Children cost only a fraction of these adult costs. The steamable broccoli was about 79 cents, and I was able to save half the bag for tomorrow/next day. Eggs were very cheap (about 10 cents each). Frozen berries in a bag came out to around 25 cents. Peanut butter came out to around 30 cents, beans were extremely cheap (less than 15 cents), and oats were pennies for my 20 gram serving.
Yes, I had to prepare it/cook it... and that does have time costs, but the fact remains, it's actually way cheaper to eat healthier foods (lean meats, good carbs/veggies/fruits/legumes, healthy fats, etc...) than most bad foods out there today.
I'm sick of people saying that eating healthy is expensive when I'm living proof it's not. It's okay to not want to do the healthy lifestyle, but I hate it when people lie to others and act like it's expensive when it's actually really cheap and easy.