The fundamental problem with "let's go teach people how to use hammers." is that then they will approach every problem as nail and try with the hammer.
Not a good approach.
The "build it and they will come" ensures people will interest and inclination comes to teh right project. Keep in mind the word "inclination". We can build interest, but without inclination we just happen to see a lot of "observers" who might evantually leave. And frankly we need do-ers more than observers.