Ok, late as it is, I'm going to explain this to my downvoter because apparently they don't understand money.
There is a pool of tax money extracted from the general population, corporations and so on, from which a small amount is taken to pay for this service. That money is taken and paid no matter what.
Assume Google don't offer to pay directly. The tax money - which includes taxes that Google paid already - is used to pay for the costs of this excursion. Google theoretically pays indirectly for the outcome.
Now we take the reality: google offer to pay directly. Their money pays directly for the whole thing. Lets assume they then write it off at 100%. In this scenario the amount of money sloshing around hasn't changed. All that has changed is that google directly pays the emergency services rather than paying that money into the general tax pool, from which the services are subsequently paid.
Either way, google pays.
The only way to see this as a net loss is to assume that the government deserves the tax money that google hypothetically wrote off, which is such a bloody stupid assumption that I don't even know where to begin.