The lie you have bought into is that destination traffic is the same as transit traffic.
The whole point of peering agreements is to stop one provider from piggybacking on another transit providers network to reduce their costs. The agreements are structured so that to reach various end points they transit the traffic as closely as possible to the destination then hand it off to the hosting network rather than hand it off at the first available point and allow it transit the other networks system.
This whole arrangement falls flat on it's face when one of those transit providers is also the major destination route for millions of customers. ISPs that provide residential service always have unbalanced traffic arrangement because the customer almost always requests more data then they send. As long as L3 and Cogent are handing this destination traffic off to Verizon at the closest possible peering point for their subscribers then Verizon shouldn't be able to request the the traffic be balanced.
The problem is that unregulated market forces have allowed monopoly providers in local markets to combine with the very limited number of Tier 1 network operators resulting in the almost immediate abuse of monopoly by the Tier 1 portion of the network leveraging the monopoly side of the residential ISP business. There is rather simple solution to this problem. Bar any ISP that offers services directly to residential customers from owning or operating long haul national networks. If Verizon was forced to separate their Tier 1 transit business from their Residential ISP business (as in either divesting the assets or separating the company into two distinct companies) the problem would be solved almost immediately.
Businesses with monopolies will abuse them, that's the whole point of regulating free markets, because without that regulation you will end almost immediately with companies abusing market position and breaking the free market. Free markets don't stay free without regulation, particularly businesses with massive capital start up costs such as residential ISPs. Without regulation you end up with Verizon's Tier 1 network business leveraging the monopoly residential ISP traffic to extract rent from competing providers. This is a rent the market would not support without the monopoly or with regulation to prevent it's abuse.