You’re clearly out of touch and over inflating numbers. $200/month for groceries is nothing but cheap carbs? $1400/month for rent? Are they living in their own 1 bedroom in the middle of the city?
$50/week in food is doable, but it takes some careful planning. I'd be impressed at someone who could purchase fresh vegetables and fruit, balanced whole grain carbs, and a healthy protein of their choice, spices sufficient to produce a reasonable variety of meals, plus some occasional luxury food items for that budget.