Customers are not asking for L3. Customers are asking for content, of which L3 is one of the providers. L3 is pushing L3, even if you say they're not.
L3 is not pushing, the customers are pulling. The ISPs serving the customers are not able to keep up.
You want pushing? That'd be L3 using (as an example) Comcast to reach customers of TWC. Then L3 would be pushing through Comcast. That's not the (apparent) situation here. The end user is on the other side of this peering divide, not multiple peers away. Customers are pulling data from Netflix which happens to be on L3. Blame the customers and up their rates if that's what's needed to cover the costs. But at $15+ billion a year in profit Comcast can probably afford to use the customers' money to provide them with the promised experience.
L3 is not necessary here, and everyone who's actually involved knows it, including L3.
Or are you arguing that an ISP should be allowed to restrict which services people are allowed to access depending on how much those services pay the ISP?
Without the service L3 provides, Comcast wouldn't be able to (as efficiently) provide the service to their customers. In a sense, Comcast should pay L3 for their access to the content.
Um, didn't someone upthread point out that Level3 doesn't actually carry any Netflix content?
You can try to package it any other way you like, but that's what you are suggesting: The only reason Comcast is in position to try this gambit is because there are alternatives (albeit very few) to backbone providers, and major content providers can be bullied directly, but most Comcast customers do not have alternatives to Comcast.
If anything, that Comcast even dares ask for this should be evidence that they are abusing a monopoly situation, and ought to be a trigger for massive reform - in a free market, they'd get told to take a hike.