1 and 2 have the same answer: it's signaling. Going to college has enough discriminatory power between good and bad workers, and it's also cheap enough for the

1 and 2 have the same answer: it's signaling. Going to college has enough discriminatory power between good and bad workers, and it's also cheap enough for the good workers to buy (behaviorally speaking, it's almost free in US. 4 years later doesn't have any weight with a mean 18 year old's discount coefficient. This also touches upon 3, everyone keeps going to college so why not jack up the price? It's not like there is any price elasticity or anything.