What customers pay is an averaged out bandwidth usage from my understanding.
They can, and should, respond by modifying their plans accordingly. Once the consumer's contract is up, renew them with a more modern usage model. Until then, you eat the cost for not doing your only job.
The theory that "we didn't build in a margin of error and therefore someone else is responsible" is dangerous to society.
ISPs SHOULD see losses. Their investors aren't entitled to guaranteed profits.
In Europe, as usage goes up, prices stays flat, because ISPs there know that the cost of a marginal bit of data is almost nothing, and they actually have to compete with each other on customer service and price.
Until you get to that last bit that your wires and equipment can handle. Then it costs a bunch of money to upgrade those to handle the extra traffic.
Cell phone plans have data tiers and pay-per-use. There's no reason cable companies can't do this either, except it prevents them from fudging costs.
I probably use as much bandwidth as anybody else, and I'd prefer to be accurately charged for it rather than have my provider pull shady net neutrality things or try to become an ad network or buy a media company to "bundle" their services or sell my data to third parties to juice their income.
I see both sides. Honestly, I think there was a better argument for it when the heavy users were a small percentage of users downloading a bunch of "Linux distributions" on bittorrent. Today, it's more likely to be a family that uses Netflix a lot.
Metering would change usage for better or worse and the fact is that a lot of domestic phone plans don't have caps, or at least meaningful ones any longer, although they may throttle data at some point.