There are a lot of good reasons to support Net Neutrality, and I agree with all of them. But there's one reason that's hardly ever mentioned--the reciprocity agreements that are inevitable between all of the major carriers.
The fact that the Big Guys will benefit from preferential treatment is a given--if you're Disney, you can afford to pay to get better exposure for your site. But the conglomerates that own content and big pipes will have an inherent advantage, in that they can set up agreements to share each others' pipes for free. This allows them to leverage their infrastructure investment to promote the content sides of their business--giving them an unfair competitive advantage.
Not a big surprise that they want to set things up to keep out smaller competition, but yet another reason to pressure your senators to make Net Neutrality law.