It is a double edged sword. You want people to start using your network and spread word of it. Nothing spreads faster then good news from a internet point of view. That wins you customers. Connect the 200 or so people that returned their contracts and they will do marketing for you. If that 200 is happy then in no time at all you will have 500. And it will win you signups at other locations around the country. It also gives them time to stabilise their network since a hiccup or two is expected.
It is a bit much to expect people to signup if there is absolute zero feedback of their network from customers and to add to that pay a construction fee and you cant use it since the network is crappy. That is what keeps the most people from sending the contract back, the unknown.
I am sure their network will be better then anything we have currently, so why not connect the people and let them do the marketing for you, for free. Yes the capital to start this fibre project must be regained, but it will only be regained if you have customers.