Basically what this is saying is that spending a lot of money, time and work in general, to organize campus/school/other events where young developers/aspiring developers attend for FREE to learn about git and other stuff... is turning out to be good and beneficial for those who attended?

Well, that's fantastic - plugging the holes of the education system is a very honorable thing. Congrats to GitHub for coming up with this marketing initiative that is somewhat altruistic and not just marketing, okay it's definitely a lot of marketing too!