He most likely doesn't have credit card debt, he's not in the practice of buying for the sake of having, he doesn't have utility bills or mortgage/rent.
So, that $800 per month is for his auto insurance, gas, propane, cell phone and food/toiletries. Figure his monthly expenses are around:
$75 for insurance
$60 cell phone
$30 propane (probably used for cooking only)
That leaves him $635 for food/toiletries and gas each month. And in the game season, he's not roaming around in his van, so he's not spending on gas and propane each month - I suspect he hangs onto the excess during that time to provide a bit extra in his off months.
He's simply taken out everything but the necessities. And when he gets injured and has to retire at 35, he won't be hocking Nike on TV.