I was very poor for several years in my teens and early twenties. Now I still live frugally as it is hard to change the habit, I still remember struggling to afford basics. I frequently went hungry and weighed only 7 stone.
Cooking from scratch, using mainly cheap vegetables and occasionally the, um, less popular cuts of meat, was one of the useful skills I learnt in that time.
DH is frequently amazed by my ability to rustle up a meal from a couple of wrinkly veg and a bit of cheese when he thought there was no food in the house and we would have to go to the shop 
People like the OP who can't imagine that anyone goes hungry enough in this country to eat that sort of food must have lived a very sheltered and privileged life 