Post-secondary education is not needed to live a good life, I think you should do what you feel is right. There are many benefits of going to college/university and getting the degrees, such as the skills needed in a certain field. But if you don't want to be anything else but work in the Fire Department, then those skills are not needed.

I chose to go into University straight out of high school because the occupation I see myself doing for the rest of my life requires the skills taught by universities. Many of my mates are still undecided about what they want to do with their lives, one of them decided to go to university with a hazy vision of what he wanted to do, and is dropping out now.

Make sure that you are certain that you do not need the necessary skills before you decide. :P