If they put out the fire, then other people would ask for the same treatment, thus rendering the whole system useless, when the fire spreaded to a neighboors house then they took action (neighboor payed his tax), there was no one at the house, from what i understand, they have the obligation to save a persons life even if they didn`t payed the 75$.
Which begs the question, what if they refuse to put down a fire and the owner decides to jump into the fire filled house?