1) Only 1 university has done this. Thus you can't really argue this is a trend
2) This is a private organization since it is a private school, thus no state funds are directly funding it.
3) They are doing it for it is a receipt of success, via standing out. They are the only university in the US to do this, thus they are standing out via asking this question. It is a "signaling mechanism"
a) They are a private university who are competing for "talent," trying to get wealthy kids to go to their institution. Even if the kid is straight he may fell more likely to go to this school for it is inclusive, and he/she may see the school as more liberal, modern, and cosmopolitan. Or a closeted gay boy/girl who is still stuck in a hell that is high school may feel safe.
When you only have 3,400 undergrads and 230 grads students, an increase of 200 hundred students is an 6% increase in revenue. (And with tuition costing 30k a year, 200 additional students is 6 million more revenue a year.)
b) It is another way for the school to recruit funds from private donors/past alumni. Look how liberal, modern, cosmopolitan we are.

When you are one of many thousands of organizations, some times it pays to stand out. Elmhurst needs to be peoples 1st pick to succeed, no one spends 30k a year on a university to be a 2nd choice pick. Elmhurst needs stories to tell to get people excited to be there besides them being a liberal art school, and only 30 mins from downtown chicago and 25 mins away from Chicago O Hare.