Why is mp3 the standard? Because it's better than everything else out there?
No. mp3 is the standard because its creators licensed it broadly to spur its adoption. Then, once it was the de facto format, they started to enforce their patents aggressively and restrictively.
The Free and open source multimedia codecs such as the Ogg family of codecs are superior, and they are not patent-encumbered. Never have been, never will be. That's why we support Ogg Vorbis (lossy) and FLAC (lossless) for general audio, Speex for speech, and Ogg Theora for video.
For those people who insist upon using mp3, it's not difficult to figure out how to get these players. Still, we'd much rather change the world instead of going along with it.