Reading on the web

I have been a bit confused over the recent opposition to Google’s project to digitise books so they would be more available on the web. There was much opposition to the project, particularly from the Society of American Publishers - presumably because Google was looking at publishing books that aren’t already in the public domain – meaning there would be copyright issues if they were to proceed. Google's project would involve digitising millions of works from Harvard, Stanford, and Michigan universities to make them searchable.
Running at the same time is a project by Microsoft and Yahoo, who are planning to put 150 works (already on the public domain) on the net.
But will putting these works on the net make people readers? Would you read more if you didn’t have to pay for it? Or is it a matter of being able to get access to works for which you would otherwise need to travel overseas for? Is the move designed to meet a niche market or is it something most of us would want to access?