Well... I don't see anything terribly wrong about it. It's not that different from what we (U.S.) do now. It's pretty morbid, but it's still efficient.
If someone is sentenced to die, and they're receiving a lethal injection (as opposed to the firing squad as mentioned), they can be killed on the way to the morgue. No need for killing someone in an execution chamber then taking the corpse to a morgue. So in effect, it's the same thing the US does minus a step.
Even still.... creeeeeeepyyyy. I wouldn't want to be the driver.