Sorry- not buying it. A junk food diet is much more expensive than cooking your own meals complete with fresh vegetables. Can't afford meat (but can afford frozen pizza)? Then go buy some chickpeas and make some chickpea burgers. Much better for you and cheaper. Want a snack - don't buy a Wendy's junior burger, eat an apple.
A junk food diet (high fat, high carb) is a sign of laziness.