Only their symmetrical 2 Gbps service is delivered via FTTH (Fiber To The Home).
I have 1gb internet from Xfinity and they claim that it's fiber optic, what I don't understand is why they did not use fiber cable in my house ans they claim that fiber cables are only used out side of the house and coaxel cables used inside the house. Is this true or I'm being ripped off here.
That's only partially true.
For most residential and business connections, Comcast deploys what's known as Fiber to the Node (FTTN), which allows for fiber optic connection to your local node, and from there coaxial cables are used for the so called "last mile" connection. Why this was decided on instead of full Fiber To The Premises (FTTP) /Fiber to the Home (FTTH) is beyond the scope of this forum.