It takes much training to be an EMT, the wages don't seem high enough. The job still attracts people though. I have in-laws that have been and still are EMT's.
They love the rush that they get on a run, they love seeing their pictures on the news (I never hear the end of it), they get to wear uniforms and talk medical lingo and think that you have no clue as to what they are saying.
Then, the part that you don't know about, on a slow day once their rig is clean and in order they get paid for doing nothing but waiting.
So, while the job doesn't pay the greatest, it has it's perks. Money isn't everything. But, lets just say that McDonalds much to your horror started to pay the same money as EMTs make, some people before having to do all of that studying and take he training would (true to human nature) take the easy route, they would go flip burgers.
Some EMTs who have had a rough few days or didn't like their boss would go to the golden arches in spite.
Emt pay would eventually have to go up to lure in new qualified people, yes, competition for employees, diametrically in opposition to employees competing for jobs. One creates demand for workers and thus higher pay, the other produces stagnation in wages.
A good solid ground floor starting wage puts money into the economy.