It's a funny thought on the surface, but the people working these scams are typically slaves, more or less. I'd rather go after their slavers than waste electricity to waste their time.
I also think it's extremely simplistic to call the people making the calls "slaves". A lot of the time, they are in facr the perpetrators. Even when they are part of a more organized operation, they (1) are likely paid per successful scam, so they are co-interested in hurting you, and (2) fully aware they are scaring and stealing from someone.
So I wouldn't call these people slaves, I'd call them low-level criminals.