AT&T bought assets with that money. They're receiving income that in theory should be offsetting what they spent. It's not like they bought a car and a nice dinner. The money isn't gone.
The money isn't gone but cash-flow is.
With this step they will have better cash-flow earlier.
Yes, raising prices tends to do that. Doesn't mean they had to in order to finance the deal. They did it because they could.