JoeHimself5 So here's the thing:
Grasshopper I believe is also doing PBX hosting, either full hosting or partial hosting much in the same way CallCentric does. Every Grasshopper number with IVR prompt is "Press 0", always has the same music on hold, etc.
I believe the voicemail at Grasshopper is carrier-hosted.
I do believe there's a split burden of cost-sharing between the carrier and the scammer for the hosted features. It takes a loooooooooong time (say, 15,000-20,000 calls) to fill that voicemail, or however long it takes for the scammer to notice all the email notifications from their carrier that they have a voicemail waiting to see that even if they turned their local PBX off, Grasshopper is still handling calls.
Given that carriers still have to pay intracarrier-fees for carrying and terminating the calls, it's still worthwhile to autodial Grasshopper numbers into oblivion until they become "parked", which is taking the number totally out of service and getting a SIP 5XX error or a carrier intercept.
Several of us have called Grasshopper repeatedly and have told them they have become THE carrier for IRS/SSA scammers using toll-free numbers. They have been slow to deactivate/shutoff on complaints about it.
It seems the only way they listen and respond is by handling traffic to these numbers until they're left with a scammer that doesn't want to pay them for the traffic.