Why would they do this? Well, if you follow the money, you can see that they are well supported by Elsevier - one of the publishers vehemently against open access to scientific research results.
For more on this see
- Elsevier-funded NY Congresswoman Carolyn Maloney Wants to Deny Americans Access to Taxpayer Funded Research from my brother Michael Eisen http://www.michaeleisen.org/blog/?p=807
- Why Is Open-Internet Champion Darrell Issa Supporting an Attack on Open Science? from Rebecca Rosen at the Atlantic http://www.theatlantic.com/technology/archive/2012/01/why-is-open-internet-champion-darrell-issa-supporting-an-attack-on-open-science/250929/
- New bill to block open access to publicly-funded research from Peter Suber https://plus.google.com/u/0/109377556796183035206/posts/QYAH1jSJG6L
- Scholarly Societies: It's time to abandon the AAP over The Research Works Act from John Dupais http://scienceblogs.com/confessions/2012/01/scholarly_societies_its_time_t.php