Oh, for sure. But I wasn't even talking about any business ventures (those are rare in astrophysics...) but more about keeping your code under wraps to prevent others from benefiting from your hard work. Especially, when (as I said in another post), code development is not especially beneficial for your career.

Though it's hard to find a situation where people don't have a (short-term) incentive to make their work look good. One can hope it will catch up with them in the long run, but more likely by then they have a new job (and, in academics, tenure) that will never hear about their past shoddy work.