I can help out a bit here as I own academic versions of several pieces of software.
To be able to purchase academic software you need to be one of the following:
1) An educational or theological institution
2) An educator (teacher, professor, ect..)
3) A theologian (pastor, preacher, priest, pope) (I believe all companies that do academic software include theologians but I could be mistaken on this....but all the academic software I own included this area.)
4) A student full or part time with valid proof of student status (usually a student body card will be proof enough but you may be asked for more)
Why doesn't everyone just buy the academic software? Simple, not everyone fits into the above catagories. Also, you have to find the right dealer who deals in academic software....you can't just walk into any place that offers Cubase and purchase the academic version. And lastly, some people aren't aware that there is such a thing as academic discounts for software. Also, the dealers who sell academic versions have to be really careful to check credentials so there is not fraud occuring, and this is something that software companies are really serious about. Dealers will lose the privilage of selling a line of software if they are caught abusing the system and letting someone not qualified buy the software at a discount.
Why do they offer academic software at a discount? Simple, to encourage educators and educational (and theological) institutions to use their product. This will in turn generate future sales from the students that use these programs in their studies that want to keep using the software either outside of class or after completing school. People tend to stick with what they are comfortable with. Apple computers started this by offering schools HUGE discounts on their computers in an effort to bolster their sales in the homes of students who used their computers, and it worked quite well. Software companies picked up on this. Also, word of mouth sales can occur. If you use a piece of software in school and really like it, and maybe you don't purchase it but you have a friend who says "I really would like to buy "(area of software you have used)" but I don't know which program to buy", what would your response be? Probably "try this software I used in school...it was really cool and works great!". Sale made.
Why theological discounts as well? I think in addition to getting in good with the "big guy upstairs" (
) it is that same mass exposure and probability of word of mouth that will lead to future sales. My cousins church is big enough they have recording equiptment and a small studio that records everything from the weekly sermons, to musical projects for the church and their members. If people see their church is using Cubase and they use it a bit and really like it, what program are they going to buy if they decide they want to do some home recording?
Anyhow, I have totally overexplained it here, but that is the deal. I learned to use Finale (music publishing) software as a Music Theory/Music Composition and Music Studies major in college and that was the software I bought to use at home. The company made a good $350 bucks off of me that they likely wouldn't have made if I hadn't learned scoring using their software.