[Austroturf]

There's a lot of questionable stuff on bowl selections in this thread. 

The conference chooses the bowl selections (as Spiny noted). 

In recent years the conference records have very closely reflected the bowl pecking order. Most exceptions are where schools asked for a flip to provide a different destination for players and fans. [My memory is that Stanford lobbied for the Sun Bowl rather than the Foster Farms Bowl in 2016.]

Minor bowl games do not make money by visiting fan bases showing up. Most of the money is TV. Participating teams must agree to purchase a bunch of tickets, which outside of some rare cases is more than their fans will buy. That hits athletic department budgets but doesn't affect the bowl's take. 

Stanford and the Foster Farms Bowl did seem to have a bit of a beef in 2014. Whatever was the reason, it wasn't that Stanford killed their meager attendance numbers. 
Foster Farms Bowl attendance (bowl changed names a few times):
2011 - 29,878  (Illinois vs UCLA)
2012 - 34,172  (Navy vs ASU)
2013 - 34,136  (BYU vs Washington)
2014 - 34,780  (Maryland vs Stanford)
2015 - 33,527  (Nabraska vs UCLA)
2016 - 27,608  (Indiana vs Utah)
2017 - 28,436  (Purdue vs Arizona)

My understanding of the Foster Farms disappointment was that the bowl organizers expected a bump in attendance because Stanford was so close.  But it was Christmas break, so all the students were gone, and the fan-base was not bunched within convenient driving distance as with more local universities.  So there was no bump, and Maryland fans actually outnumbered the Stanford fans.  But, yes, as can be seen, the attendance numbers have flagged regardless of the participants.  If there was any other beef, I am unaware of the causes.

[Austroturf]

There's a lot of questionable stuff on bowl selections in this thread. 

The conference chooses the bowl selections (as Spiny noted). 

In recent years the conference records have very closely reflected the bowl pecking order. Most exceptions are where schools asked for a flip to provide a different destination for players and fans. [My memory is that Stanford lobbied for the Sun Bowl rather than the Foster Farms Bowl in 2016.]

Minor bowl games do not make money by visiting fan bases showing up. Most of the money is TV. Participating teams must agree to purchase a bunch of tickets, which outside of some rare cases is more than their fans will buy. That hits athletic department budgets but doesn't affect the bowl's take. 

Stanford and the Foster Farms Bowl did seem to have a bit of a beef in 2014. Whatever was the reason, it wasn't that Stanford killed their meager attendance numbers. 
Foster Farms Bowl attendance (bowl changed names a few times):
2011 - 29,878  (Illinois vs UCLA)
2012 - 34,172  (Navy vs ASU)
2013 - 34,136  (BYU vs Washington)
2014 - 34,780  (Maryland vs Stanford)
2015 - 33,527  (Nabraska vs UCLA)
2016 - 27,608  (Indiana vs Utah)
2017 - 28,436  (Purdue vs Arizona)

My understanding of the Foster Farms disappointment was that the bowl organizers expected a bump in attendance because Stanford was so close.  But it was Christmas break, so all the students were gone, and the fan-base was not bunched within convenient driving distance as with more local universities.  So there was no bump, and Maryland fans actually outnumbered the Stanford fans.  But, yes, as can be seen, the attendance numbers have flagged regardless of the participants.  If there was any other beef, I am unaware of the causes.