I think a lot of it is also just a general amount of fear for (from the companys perspective) no benefit. There's a lot of fear that if the code is visible, you

I think a lot of it is also just a general amount of fear for (from the companys perspective) no benefit. There's a lot of fear that if the code is visible, you could be sued for its contents or it could be otherwise used against you in court, competitors could "steal" your effort, etc. Plus there's just a lot of belief in the nonfree circles that the software freedom movement is just religious zealot hippies who think software should never be paid for and that microsoft programmers should work for free and starve, and that anyone who does develop novel software should have it immediately ripped off and copied by competitors and make no money because capitalism is bad. (I'm being a bit hyperbolic but not much.)