If you live in a long road you could stand there for hours - that's just not practical. My brother-in-law came round earlier - we said goodbye at the door, then I shut the door as he got in his car and drove off. I can't see why it matters.
If it's someone I haven't seen for ages and really care for, then yes, I would go out and wave the car off - it really depends on the circumstances. Thre's no set etiquette about it.