Suppose they did help and one of the firefighters got hurt. It would probably be a violation of their insurance ("Why were you protecting a home not on your coverage list?"). Would the family who was too cheap to pay $75 a year pay for medical costs for that firefighter?
Most unlikely. The insuredness or not of a property has little bearing on the dangers it poses compared to any other burning building; it's the accountant who'd be upset, rather than the insurers.
When buying insurance for providing a service (especially a dangerous one), there are often conditions about the place these services may be performed and under what condition. It is pretty likely that their insurance policy will only cover them on homes that they are paid to protect. It might also be the case that a certain percentage of each yearly payment goes to insurance.
Indeed, but the judgment call about whether a fire can safely be fought would rest with the experts - firefighters.
If I own a very poorly maintained property but my $75, they may be obliged to turn up but I can't force the firefighters to enter an obvious firetrap just because I have a receipt for my payment. They'll do the best they can under the circumstances. The payment or non-payment of a premium tells you nothing about the safety risk of fighting a fire in any given building. Look at some worker's comp policies and you'll find the conditions revolve around the activity performed rather than exactly where that occurred. Otherwise you'd need to assess the financial risk for all possible firefighting scenarios in advance.
Here's an example application for insurance for a volunteer fire department (I can't give you a contract offhand because they're unique to each FD). The insurance company does ask what you claim, but this is in order to calculate what the premium should be. Note that this draws no distinction between whether or not lives are at risk from a given emergency call. If a FD has a policy of responding when that is the case (which they normally would), then the insurance is going to priced to include that anyway. Calls to which a response is purely optional probably make up a tiny fraction of the total, and would have a correspondingly marginal effect on premiums.
Actually, the ultimate judge of the actions would be a court not the firefighters. The insurance company would have a good case that the firefighter was hurt trying to protect a non-client and isn't responsible to pay-out insurance on the firefighter's injuries.
As you say, if lives where at risk (not in this situation) and the charter and insurance policies noted the exception, then the insurance company would be on the hook for injury payments. This case didn't involve a person in danger and would probably give the insurance company a very good case for not paying.
OK, but when you're considering whether and how to fight a fire in a burning building there's no court to make the decision for you; and even afterwards, all the expert witnesses are going to be firefighters talking about the particular risks presented by the particular structure.
If the insurance policy draws a distinction between whether or not lives at risk when a non-subscriber's call is answered, then the insurance company may have a case as you describe. But your comment seems to assume this is the norm, whereas the questionnaires I've looked at don't make that distinction.
Remember such insurance policies (issued to a FD) are upon life and limb, rather than on department revenue stability. An insurance company would challenge a payout if they felt the fire department (perhaps because of bad training or staffing policy) foolishly ordered a crew into an impossibly dangerous situation resulting in injury or death, even if the property owner was a paying subscriber. In reality, fire crews sometimes have to let a property burn and just try to stop the fire spreading, because the presence of chemicals or an unsafe building structure makes it too risky to enter.
