I suspect the reason for this lack of opposition is that the current situation suites big business (for the moment, that may be changing) whilst small businesses have neither the money, time, people or culture to do lobbying.
The opposition or lack thereof to a law from business doesn't make the law right morally nor economically. On the moral front businesses have been (and in some cases still are) in favour of behaviours few would consider acceptable such as child labour and slavery.
Imagine for the moment a perfect legal system capable of enforcing patents automatically at zero cost. I think most people would agree that given many of the current software patents that have been granted on trivial things software development would then become impossible. Therefore the current system only "works" because it is only imperfectly enforced. I would say a law that only works because it is not enforced most of the time is fataly flawed.
Furthermore software isn't just about business (big or small) since private individuals can be involved (and ultimately their creations may become very important as in the case of Linux) the views of all software developers should be considered.