He wants a culture of constant healthy developments to the ecosystem. Good content is not cheap to produce.
Any bug fixes should be free, of course, but the kind of stuff many want, like content, should cost money because we want it to happen throughout the future.
There's a fine line here. EA often sells games with half the content locked so you have to pay DLC fees for it. That's unacceptable. Some games however will give more real content for download if you pay, like Bethesda's DLC of new areas to explore. That latter stuff is valuable to the hardcore fan.
Anyway, end of the day, I do want PD to make money.