That's excessively expensive.
In NL, we don't have fiber everywhere (yet) but we do in most populated cities and the likes. Reggefiber (and possible other infrastructure providers) lay down the fiber lines _all the way to the time_ (FTTH, fiber to the home) and this is generally without cost to the person renting the house (afaik, most people in NL rent ; don't have metrics to back it up though) I'm unsure, but I'm guessing the corporation who actually owns the houses pays for the FTTH installation.
Then ISPs lease the fiber lines from the infrastructure providers (i.e. reggefiber) and provides the customer with a ONT (optical network terminal) and a modem. The fiber goes into the ONT, connectivity via (U|S)TP comes out to the modem and from there on you're all set.
So all in all - ~75 euro/m for 500 Mbit/s duplex is extremely cheap compared to xfinity's offering. You'd be better of with Google Fiber if it becomes available in your area - not just because it'll be cheaper for 1Gbit/s but I dare to bet that Google would provide better customer service than Comcast is known for.