[Embo]

Another factor which relates to attendance is how many alumni live within reasonable proximity to campus. For example, I'm sure that a significant portion of the Nebraska alumni base live within driving distance of Lincoln, whereas a significant portion of our alumni base is scattered throughout the country (many on the east coast) and overseas.

That is indeed a key point.  Not only is Stanford's undergraduate student body small, it is definitely not local.  The percentage of freshman from California has been dropping slowly but steadily - the most recent data from the freshman class entering Sept 2015 was 36%.  And that is from the entire state.  To guess that 50% of the freshman from California are from the southern California area would be an underestimate.
I remember looking up the demographics of the C.al freshman class several years ago during one of those our-attendance-vs-yours thread wars.  It was striking - a near majority of C.al freshmen come from Alameda/Marin/San Mateo/Santa Clara counties.  They should have no problem filling their stadium

[Embo]

Another factor which relates to attendance is how many alumni live within reasonable proximity to campus. For example, I'm sure that a significant portion of the Nebraska alumni base live within driving distance of Lincoln, whereas a significant portion of our alumni base is scattered throughout the country (many on the east coast) and overseas.

That is indeed a key point.  Not only is Stanford's undergraduate student body small, it is definitely not local.  The percentage of freshman from California has been dropping slowly but steadily - the most recent data from the freshman class entering Sept 2015 was 36%.  And that is from the entire state.  To guess that 50% of the freshman from California are from the southern California area would be an underestimate.
I remember looking up the demographics of the C.al freshman class several years ago during one of those our-attendance-vs-yours thread wars.  It was striking - a near majority of C.al freshmen come from Alameda/Marin/San Mateo/Santa Clara counties.  They should have no problem filling their stadium