In the referenced message, Greg Pendergrass said:
It doesn't make sense that an ISP should complain that customers use 100% of what they pay for. So if 1% of your customers use %50+ of your bandwidth, your 1% is getting their money's worth. If you don't want the customer to use it, don't sell it to them.
The point is that customers don't pay for 100% of the available bandwidth. Customers couldn't afford to pay for guaranteed 100% BW to all desinations all the time. Hence, companies determine how much BW a typical user is likely to use, build to that, and charge the customers based on how much it cost to provide it. When folks use the service atypically, they are using resources they didn't pay for. If you think otherwise, build a company that doesn't aggregate flows, and gives every customer (simultaneous) guaranteed MAX BW 24x7 to every destination within their network and at least the first-hop into non-customer networks.