Residential internet connections aren't designed for the same kind of usage as some VPS.

Ok but we’re talking about a whole computer with redundant power and connectivity and memory and disk storage compared to throughput on already-installed non-redundant wires. One of those certainly costs way less than the other, but Comcast still charges multiple orders of magnitude more for.

Its not a whole computer, its a tiny fraction of a whole computer. And that whole computer is in a giant datacenter hundreds of feet from massive ISP interconnections and only a few hops of hardware away from it. Meanwhile the residential customer is probably many miles from the nearest interchange, often even hundreds or more miles.

Location, location, location.

I do agree the over the cap costs imposed by residential ISPs are many, many multiples of their true cost, but they're mostly there to discourage use not be a reasonable price. If you want business level usage hop on their business networking where pricing models are more designed for more average load.