Why bother paying insurance for devices??

I have a wifi modem that has a swollen battery. The modem is under warranty and is insured. When my daughter took it to Vodacom at Eikestad Mall, Stellenbosch they were so pathetic they could not even tell her whether it was under warranty or insured and sent her away. When she returned with proof it was under warranty and insured they shuttled her back and forth between the 2 Vodacom shops in the Mall. Eventually they accepted it as a warranty repair and told her it will be ready in 3 weeks. My problem is that besides the pathetic service, she does not receive a new replacement device. What am I paying monthly insurance for?? Secondly, if Vodacom does not replace the device (which I feel should have happened), why can they not give her a loan unit so she can at least access the wifi that they are continuing to charge me for??