Because these decisions are made in pieces by a society, not by a few idealists in binary. That's just like saying, "Why not stop listening to ASCAP music?" It's almost impossible to avoid AP content at the moment and will remain so for the near future. And that's the problem with behemoths in many cases -- they're not nearly as sensitive to market pressures and so often end up being idiotic while society changes around them.
"It's almost impossible to avoid AP content at the moment"
I don't see any problem for a blogger to stop linking to AP. Not wanting to be linked to is a very stupid wish, so instead of trying to "educate" AP it's much simpler and more appropriate to fullfill their wish.
The problem isn't with getting some individuals to act on this. The problem is getting society as a whole to do so. This is a general problem with trying to incite a boycott of something that has very widespread usage: the dent you can make is often too small to be noticed, because society is too hard to organize.