In locations with high population densities, there is nothing you can do to LTE to provide adequate service.
Looking at where things are going right now, the current MNO model is not sustainable, given the amount of capex that is constantly required, the declining margins, the change in the kids' online behaviour and the constant (or even rising) equipment costs from vendors.
If the MNO model of pure infrastructure play is how they intend
to keep doing business in an age where transformation away from it
is forcing networking businesses to re-think the (true) value they
offer to customers, SP Wi-Fi seems like the logical way to
maintain said business model. Either that or pull an Amazon and go
from selling books to... well, you know the rest :-).