$20 million buys a lot of child care, health care subsidized planning, or other goods that can be negotiated down in price when contracted in bulk. The benefits of those can do a long way in making people's lives better.
That's ridiculous, he's not talking about buying those pizzas directly, but the employees buying the pizzas across the country. That money goes to the pizza chain, the deliverymen, the local pizza franchise employees, the managers up to the top; and then all of those people spend part of that money, and onward.
The bigger deal is that the more realistic scenario for the CEO is that he spends a few million but sticks most of the $20 million in a hedge fund where it goes to play abstract high finance games that maybe add some liquidity to that international market, but doesn't do much good otherwise. The money doesn't get spent anywhere, doesn't create any jobs other than maybe a few on Wall Street, and creates a generation of entitled trust fund do-nothings of his kids, rather than have them forge their own ways through hard work and entrepreneurship.