Because that's how most of them are.
I started as a volly in Eastern PA, in a county where the 911 job numbers are going up and up. I sat at the station whenever I was on duty. By myself, since everyone "responded from home". And you had 10 minutes to get a BLS unit out the door.
Nothing like sitting on scene as a paramedic, waiting for BLS to show up, because you can't transport.
Nothing like going enroute, where BLS is screaming for ALS, where not only you have an extended ETA, but the vollies think it's better to sit on scene and wait for you, as opposed to load and go to the hospital which is 2 BLOCKS AWAY.
Nothing like getting called into the office, since the same vollie crew called and bitched after you tried to turn above situation into a learning moment, telling them diplomatically that once you realize you have a patient require ALS, it's better for the patient if you load and go to the hospital.
Those who say call numbers don't justify a paid crew, there is a simple solution - REGIONALIZE. Drop the f--king egos and work together like a real team. If you're really in it to help people, do what's best.
And on top of that, if you wanna see Volunteers Gone Wild, go to Jersey, where if you're part of the NJFAC, you don't even need an EMT on a volly "squad rig" to go to a job.