For all we know, it could be a conspired deal between telcos to make more $$$.
Telco A makes things so unbearable that the user breaks one's contract (if any) and jumps ship to Telco B. Telco A already has too much congestion for overselling and doesn't mind losing a consumer. But Telco A gladly accepts a new customer to meet their quota through aggressive promotions. Whichever way things go, Telco will get its $$$ from either penalty fee or new subscriptions. At the same time, Telco A will deliver ex-customer to Telco B. Both telcos win but the customer loses. Why? Telco B probably screws the customer down the road by employing similar tactics as Telco A. Customer returns to Telco B. And everything goes in circle.
So much for conspiracy theory and talking cock.