I would say if you assume that markets don't regulate themselves to the best, the argument that users should not care, is not valid.
Or put it the other way: if users don't care, they will be exposed to changes / forces they don't control nor want.
I think this is very similar to political activity: if you don't vote, your life will be more influenced by the opinions of others.
If you vote (care), then you can make a change