Well, that depends what you mean by going "commercial."
You can't simply switch a non-comm to a commercial license. To say the least, the FCC would not be impressed. Most non-commercial stations fall between 88.1 and 91.9-the non-commercial band- and by law these stations must remain non-commercial and non-profit. I could write a novel on the difference between the two types of licenses-but in short-you cannot have advertisements on non-comm stations (It's also difficult -due to FCC regs- to do a lot of the promotional things you hear commercial stations do).
As for why colleges don't adopt a commercial sound--I think that's a case by case decision. Schools with strong broadcasting programs often do have commercial "sounding" stations-check out Ithaca and Emerson to name a few. There's a Catholic university in Albany that images their station as "The Saint".
Other schools often try to have their stations be more educational or community oriented as a public service-this especially beneficial if the academic broadcasting program is more focused on journalism or public policy.
Schools with no or a limited academic program for broadcasting students are often more interested in making sure there is access to the airwaves as a fun and educational activity for students of all academic concentrations. Colleges are usually very concerned about diversity--and nothing shows diversity better than a folk show following a rap program on their non-commercial.
I'm not sure what you see as benefits to having a commercial sounding college station. As I stated above, if the school is looking to turn out broadcasters having a professional sounding station is a large benefit. Otherwise, financially, the sort of imaging, production, music scheduling and management required for the commercial sound is not cheap. Most of the non-profit entities that own non-commercial licenses simply aren't interested nor have the capital for that sort of investment. And of course, as I mentioned at the begining of this response, they also aren't interested in negotiating the very complicated issue of underwriting versus commercials.
Hope this answers your question!
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As for my soap box moment:
Yes, I started out at a non-commercial college station in high school, managed my college station and now work full time in radio at a commercial station. Trust me--it's better keeping non-commercial sounding non-commercial-in college, I played what I wanted. While I love every day "at the office"-when I'm on the air, I'm usually voicetracked, I never get to choose the music, and a lot of my breaks are scripted. Students driven to sound professional I support--but their drive to sound "like the big guys" is unfortunate-and many times-misinformed.
> I was wondering, what is the big deal with turning a non
> commercial college radio station to a commercial station?
>
> The people who work for non commercials often go to work for
> commercial after they graduate, so what is the big deal? And
> why don't many non commercial college station's see the
> benefit in being more commercial?
>