A part of programmers's job is to chose most appropriate tools to get the job done. It equally applies to hobbyists and professional programmers. However, licensing terms does not cause quality of tools and their documentation, it could only correlate to some extent.

The barrier you're talking about is research/learning cost. When you - for example - already have some knowledge of MS stack, unknown lands of GNU or Apple would even feel alien, so cost of using it would be higher. The opposite would be equally true. Just imagine an iPhone developer being offered to use MS stack, instead of Apple's one he's already used to.

Then, there're also personal tastes...