It will never happen. Giving out free bumpers would be admitting a problem.
Either will an online petition.
Seriously, when has an online petition work?
they can charge for shipping if they would like.
or they can just fix the phone...
You think a bumper will solve your problems? Watch this (My video)
http://www.youtube.com/watch?v=RFWVih5e_J0
No, definitely not. When I merely touched my 3G or any of my previous phones, they did not drop calls.