I am trying to find a same as to this story.
Seems when one signs up for frequent flier miles this is a contract, you fly the airline and received points. Contracts cannot be changed with out both party's agreeing to the change.
Any violation of the contract by eather party may mean breaking the contract but the one that breaks the contract cannot benefit from it.
So this family had a contract with an airline that in fact offered a trade, you fly us and you will get frequent flier miles. When one fly and buys a ticket they expect to get from here to there safely and their luggage with them. When the airline cannot deliver their promiss to do so, a complaint is in order.
To try to cancel this contract for anything but illegal activity or show harm to the airline is in itself illegal.
One cannot cancel a contract because the other is a pain in the ass and expects them to live up to their part of the contract.
This family lived up to their part of the contract, the airline did not do so by loosing luggage and sub-par service. The family complained but so do thousands of others.
The value of the frequent flier miles is huge, the family earned them, to take them away is corporate theft.