It's due to cost
I have Verizon FIOS in my vacation home and the amount of kit they installed in the garage to terminate the fibre is quite ridiculous and looks very expensive indeed. There's three boxes I believe and several cables between them. The cost of the kit and the time to install it must have been pretty high. I can quite see why Verizon are not extending the FIOS network with what each house installation must cost them.
So either they need to simplify the in-home installation to the point where the in-premises equipment is as cheap as DSL and installable by the user, or they could do what is proposed here it seems and share a single fibre to copper interface link between several houses and amortize the cost over say 10 houses. Makes economic sense to me. Sure, fibre to the home would be better, but the termination kit needs to come down in cost and simplify. Installing fibre connections isn't currently an end-user job.