This isn't just about his poor choice of rations. Look at the big picture. Why does he order pizza? Because cooking requires going out and shopping for food. Why does he have it delivered? Because otherwise, he would be stuck going out to pick it up himself, which he hasn't done once in 5 years, even though the store is just a 5-minute walk from his house (gotta love the internet). Why does he pay with a cheque? Because paying with cash requires going out to a bank or ATM to pick it up.
So here we have a 50-year-old man who is divorced and rarely sees his only son. He spends his entire day at home watching TV, which is also why he doesn't have any friends. He doesn't walk or exercise, because no 210lb man who does can survive on a 2-topping medium pizza a day. Every single day he wakes up, eats some pizza, watches tv, eats some more pizza, watches some more tv, finishes off the pizza and goes to sleep. And you don't find this depressing? Does this sound like the kind of life you'd like to have when you're his age?