[aopinthesky]

>>>Why make girls feel like they have to join a sorority that is not right for them in order to be a part of greek life simply because the other sororities did not make total<<<

You don't say whether you are a member of an NPC sorority, but it is not the "NPC way" to open campuses for expansion or encourage a campus to raise total (by much anyway) if there is a struggling NPC group there. Of course, if it is obvious that the struggling group can't move forward that is a different story, but the first plan of action would be to give them a chance to do so.
Women SHOULD join the group that they feel is right for them, but who is to say that the sorority of the moment would bid them anway? It is a mutual selection process. Just because you have a group of girls who say "we only want to be XYZ" doesn't mean XYZ feels the same way.
That being said, I am speaking strictly of NPC groups and the campus panhellenics that govern them. The situation at your school is a bit different, however, since only one of your sororities is NPC. Do those groups recruit together? Has anyone spoken to the greek affairs person at your campus about opening for NPC expansion? Perhaps one of the existing locals would be interested in going national, which would certainly expand the possibilities for everyone.