From that it seems that worldwide, 61% of commercial aircraft accidents occur during first or last stages of a flight, so there's a reasonable chance that if it happens, it'll happen at an aerodrome (where the firies are).
An interesting spin on the stats, Traffic.
There's a "reasonable chance" that it will happen
in the vicinity of an aerodrome, not
at the aerodrome. There's also a
high probability that, if an accident happens, it will be a mid air or something at high speed, as a consequence of which everyone on a disabled aircraft will almost certainly be
dead.
This is
not to say that it's
impossible for a fire to break out or accidents to occur
at aerodrome during which lives could be saved by an RFFS. E.g. runway collisions in poor vis might not kill all POB. Nor is it to say that it's fantastic to have firies on standby if someone has e.g. an undercarriage warning that means there could be a problem on landing. But it is to say that those millions could be spent on mitigating risks with greater probabilities.