Dryers are often in the garage or in the small room adjacent to the garage that we called the "service porch" when I was a kid. I think it's because the garage is a good place for the main junction box (near the street, where the main power lines are, but indoors so creepers don't mess with it), and since 240-volt wiring is thick and expensive, it's cheaper to put any 240-volt outlets near the junction box.
QED.