This may be redundant but here goes.

The answers to your questions are not cut and dry. A LOT of it depends on the university and its climate. For example, there are many private schools and a few public schools that do not want NPC or NIC GLOs on their campuses. Trinity University in Texas and the Mississippi University for Women are prime examples.

Why do locals form where nationals exist? - Sometimes the existing national groups do not fulfill the needs of the Prospective Members. If that 12th NPC sorority was on campus then perhaps more women could fit there, but there are only 11 NPC sororities. The existing sororities do not offer what the Prospective is seeking.

Alumni support can be just as good or as poor as a national's can. If the alumnus had a good collegiate experience, he will give back in time, money and other resources. If he didn't then he won't. My friend has been trying to start an alumnae chapter of her NPC sorority for years. Headquarters' sent her a list of more than 300 other alumnae in the area. She has phoned and done mass mailings and does get some positive response, but in the end it is she and one other person. Often, it is not that same one other person. There is a lot of "I was an ABC" and not enough "I am an ABC".

Effective chapter programming, just like a national, keeps these groups from becoming cliques. There are many resources that locals can tap into for assistance in these areas.

"Why form a local with the sole purpose of becoming a colony for a national?" These types of locals want what a national organization can provide, but there is no opportunity at the time. They wait until the time is right for a national to come to campus and are very often the reason that a Panhellenic opens for an expansion opportunity.

"There are colonies established without first being Greek." This is very true. When a national seeks to expand on a particular campus or a campus is thinking about adding another group, it looks at a variety of issues. The most important issue is "Is there a NEED?" A local can provide a good answer to that question rather quickly. Yes. If the current organizations met the needs of those students, the local would not have formed. A local shows that there are students with an interest in Greek Life, who can function as cohesive group.

The benefit to joining a local Greek org vs. a national/regional depends on the individual. It depends on what they are seeking. The same thought process is used when deciding to Preference Sorority "C" over Sorority "A".