I have the opposite view to most here. In my lounge is Axminster's Super Dartmoor. It cost me £XXXX. If Jasona, b or c were to clean it and cause damage beyond repair, then I would expect it to be replaced with an identical carpet of at least the same condition and state of wear as prior to his arrival. Anything less would mean that I would have suffered a loss even though the carpet had been replaced. What is the chance of anyone finding the same carpet as mine, in the same condition but second hand? Virtually nil. I would not be interested in financial compensation. I want my carpet!
Why liken this scenario as discussed with car insurance? It's quite removed from furnishings. A closer comparison would be House Contents insurance. Most of these policies will replace old with new as it's the only practical way to obtain client satisfaction.
Safe and happy cleaning:)
Ken
PS Even with motor insurance, replacement parts will be new, not second hand.
PPS If I had chosen an NCCA member to clean my carpet, I could rest assured that not only was he/she suitably trained, but also carried Treatment Risk Insurance.