"Troy isn't an agrarian village. It's a highly developed and successful city in metro with office towers up to 25 stories, a world class mall, expensive mansions with some of the richest people in country and yet they still have a voluntary fire department. Geez, it's completely irrational for something like that to exist... "

It has almost nothing in common with Detroit. Most of Troy was developed since the advent of modern fire codes. Most of Detroit was not. The homes in Troy aren't packed on top of each other where a fire in one can quickly spread to others, as happens all too often in Detroit. Troy doesn't have thousands of abandoned and vacant buildings, many of them fire traps that can collapse at a moment's notice. Troy doesn't have a population that lacks the ability to pay for basic medical services and relies heavily on emergency services to address all levels of emergency care. In short, Troy is nothing like Detroit.

"Voluntary fire departments work in highly developed and successful cities on the other end of the spectrum."

Which cities are those? There are hundreds of cities with populations of the size between Troy and Detroit. How many of them rely on a volunteer fire department?