They allow or disallow it? The question itself doesn't make sense. If the users want to use capacity they bought and Comcast sold, is the user's right. Comcast didn't foresee the demand is error of their actuaries. A insurance company pays up even if their actuaries make an error. Comcast doesn't get to externalize their costs, they could try, but we as customers have no obligation to honor it. I would claim that video demand has actually made the equation very simple for them with higher build out but lower risk of it not being utilized. The demand is very predictable and not "unexpected". And, monthly quotas (1TB per month) on top of bandwidth limits (150 Mbps) the risk is quite reduced. If someone with 250 Mbps ran at 99% capacity, 1TB quota would be over in less than 11 hours.
It's not as if Comcast sends you a check every time there is a network congestion and you don't get top speed that you are paying for. There is no consequence of congestion for Comcast but they are using it as a reason to get ransom from content owners. They are setting up the conversation such that they have less and less reason to remove congestion, more the congestion, more the end user suffer, more the case for google and netflix to open up their wallet.
$70 a month is same as cable bill and for cable Comcast has to pay channel operators. On internet, Comcast doesn't even have to pay to youtube or netflix. I mean internet service is pure profit compared to cable which runs on same infrastructure. They charge to take traffic at exchanges, one 100 byte URL in browser results in 2GB of data transferred from Netflix. It is a request that Comcast customer is making, trying to use the bandwidth and quota that the customer purchased, but Comcast makes money at exchange because they take on that 2GB of traffic. So they are already compensated for taking this traffic on both ends, by customer and at the exchange. Now on top of that they want to pry open the communication channels and charge more to the two parties talking. That's triple Comcast tax.
Comcast runs their cable programming on their tcp/ip network as well, so they are provisioned enough for now. If net neutrality goes away what promises youtube/netflix has that Comcast won't prioritize their xfinity platform over netflix?
The customers are using the capacity that they wanted and bought, Comcast sold that capacity, they must deliver. They are having no problem delivering so far. Networking gear (merchant silicone switches and OpenCompute switches) are dirt cheap, gone are the days of buying expensive gear from Cisco and BigIP. Cheaper networking hardware is making it easy to operate and upgrade for Comcast. Same goes for cable boxes, DVRs. Seen the disk prices lately? A raspberry pi can be effective cable box. Their unit costs have gone down significantly. They are benefiting from Cloud platforms like everyone else. Netflix uses AWS, Amazon uses AWS, Comcast uses AWS.
Look at hosting bandwidth costs, look at CDN bandwidth costs, content providers are paying for their side of it fairly. Comcast has a large share of CDN and can get even bigger there.
I think content providers should pick a month and ban entire Comcast network for a month together. Users will switch to shitty stuff that phone companies are selling but at least Comcast will learn a lesson. What do you think would people chose to watch xfinity or would they switch to telco ISP?