I think I'm missing something then. If that were true, wouldn't you lower the network allowance and then make the product cheaper or at least priced the same? This would have the no-traffic users paying "their fair share" and the overage costs (or higher traffic addon) would make up for the heavy users.

The current plan makes everything more expensive for everyone. They would do this if a) they never had a sustainable model in the first place or b) they were just being greedy