There was a useful open-source library that an engineer wanted to use, where I work. We had to reject it because the open-source license had been amended to include prohibition against being used by "greedy capitalists." While we don't consider ourselves "greedy capitalists" (and, in fact, we are occasionally accused of being liberal socialists by people on the internet), it wasn't clear what the exact legal implications of that statement were. So, we rejected the use of the library as "not having an enterprise-compatible license." It had nothing to do with the library being free or open-source. It just had to do with the fact that we didn't want to go against the terms of the license and couldn't be exactly sure what those terms meant in the eyes of the author.

There are two problems with the "DON'T BUY THEIR MUSIC" idea.

1) The RIAA represents many companies so it is not likely to go out of business just because a few of its member companies are hurt by a boycott.

2) If you boycott the RIAA member companies then they will just claim that their losses are due to piracy on the internet and will say they need stricter DRM and fewer online stores to combat that trend.