My theory about the home being in a zero lot line subdivision is that builders do all sort of screwy things to avoid penetrating the wall on the property line in a zero lot line subdivision. In most zero line subdivisions the homeowner of the adjacent property is required to maintain the appearance of the neighbors wall (Paint it.) on the property line unless such maintenance is include in the HOA Fee.
Never heard of zero lot line before. Guess maybe that is why the ran the dryer vent that way. You would think running it to garage roof would be better. But then that pipe sticking out the front might be considered an eyesore.