The G.fast is sit next to FTTC cabinet (mini G.fast cabinet) I am not sure! That's what I think!
see here: http://postimg.org/image/ltwpjoxcl
There are plenty of homes within 100m, 200m, whatever, of the existing cabinet, so plenty of potential subscribers. And, of course, both fibre and power already reach that site, making it cheap to install a G.Fast node. Why wouldn't you put your first node there?
Of course, putting one node there doesn't stop you adding more in other places. The question is 'where?'