Does usage based billing truly make sense for an ISP like Comcast? If it's 4 AM and Comcast's network is mostly idle, does it matter how much bandwidth you use

Does usage based billing truly make sense for an ISP like Comcast? If it's 4 AM and Comcast's network is mostly idle, does it matter how much bandwidth you use? Likewise, if everyone in your city uses their 300 GB between 5 PM and 8 PM, Comcast ends up having to spend more money to upgrade their network (or they just provide shit service). I wonder if some kind of billing during peak hours makes more sense. Taken to an extreme I think you'd have pricing like Uber's demand-based pricing, which is really "fun" to think about. Edited to add: Not that I want this at all! I'm just saying that billing based on network utilization seems to make more sense to me, since the bits on the cable are essentially free once you've got it set up. It quite possibly makes Comcast more money to bill based on bytes, and it's probably much easier to explain too.