Why do you think that a non-profit model is outside of the market? People donate money to sustain something they get utility from, and all of the donations are freely given. It would only be outside a "market model" if Wikipedia were funded solely by the government. As it were, it is a free enterprise with a goal other than profit.

Charities and non-profit foundations can hardly be considered outside of the market model. Wikipedia is, in fact, an anecdote you'd point to if your goal was to debate that market forces result in collective good.

That's true. I suppose more specifically Wikipedia is an example of web content being produced without a profit motive on the part of the producing entity, but not wholly outside a market model.

How that relates to market models producing collective good depends on which one you subscribe to. Many proponents (dating back to Adam Smith) argue that it's the profit motive in particular that makes the market model produce good outcomes. There's also a lot of skepticism of even voluntary collective production in much of the libertarian literature; e.g. the Israeli kibbutzim or the 19th-century "utopian socialist" communes aren't viewed favorably. Wikipedia has a sort of voluntary-collectivism feeling to it as well, from that perspective, though it's more limited in that you don't have to actually move to Wikipedia and live there; you can just contribute some content now and then.