Whatever their interests are, I'm certainly not knee-jerked opposed to them since I like their products and I like the effects that companies with good products provide to the economy.
At very least I think that corporations serve as a contrast to the inordinate megaphone that politicians, celebrities, and the mainstream media have.
Really, I don't think that the protestations against corporations contributing to the political process are all that well thought-out. Should Michael Moore no longer be allowed to make his documentaries? They're blatant political commercials. How about Sean Penn? Should he be muzzled from being a political spokesperson since he has such an inordinate amount of influence vs an individual citizen?
How about news organizations? Every single one out there has some sort of political bias. Should they be allowed to blatantly support political parties and candidates?