Essentially since the ISP is having trouble collecting more money from heavier users, they're angling for Netflix to charge these users more then collecting that money from Netflix
Meaning the ISPs are too cowardly to actually charge the *users* of said bandwidth, i.e., their customers. They would rather try to foist that charge off on another party with whom they have no business relationship and to whom are not providing any service, and have that other party deal with the bad PR. That's bullshit - Netflix is already paying for the bandwidth they use and has already spent a lot of money attempting to mitigate everyone's costs (via colo'd cache boxes), and if the ISP is not happy with the amount of bandwidth their customers are using, they need to charge *them* more, not Netflix. In the process they can also explain to their customers how oversubscription works, and that the new charges are a result of their own poorly-thought-out business model. Bonus points if they include information about how much they're already subsidized by the government in the form of rights-of-way, municipal franchise agreements, etc.
Given that half of all internet traffic comes from Netflix and YouTube, it's going to be a hoot when they start obtaining metrics proving their traffic is being throttled by the ISP, and providing said proof to customers that complain about the resulting sub-par video experience, and it will be trivial for them to do so. The ISPs may find their bargaining position isn't as strong as they thought if customers start cancelling or downgrading their cable/DSL subscriptions as a result.