I would think that in order to get any real deals the fiber would have to be terminated somewhere a bunch of ISP/carriers could easily cross connect to it--a CoLo is an example. Which means it needs to be run and maintained once it leaves the property. If the fiber just terminates on premise then ISP/carriers would have to build out to it (or lease someone else's fiber) thereby limiting your choices.

You brought up an interesting idea I'm looking forward to learning how this works out.