It’s encouraging bad diets. Free pizza is a way to tempt people, and the consumer of said pizza incurs an opportunity cost since they could have used the time to eat something nutritionally appropriate.
I absolutely do not need a total stranger deciding for me what is nutritionally appropriate for me, all Big Brother style.
Has a decent mix of protein, fats and carbs in a tasty package. Not everyone wants dry lean chicken, or zero-calory veg/shrooms, even if any two people here could agree on what is “nutritionally appropriate”.