I think you are oversimplifying. After all, the map data isn't really the product here. But you are right the tricky thing would be to maintain an incentive structure.

Waving hands wildly: imagine a mapping database that was owned by the government, free to use for non-profit uses, and licenseable by corporate entities. Here's the twist though, the license fees are proportional to the government doing a certain amount of upkeep/improvement on the database, and you are free to provide the same work block instead of a fee. That way, if you can do it cheaper, it will save you money up front and if your competitor can't do that, it's a competitive advantage.

I haven't thought about this model carefully just pointing out it isn't necessarily as black and white as you suggest...