When you're travelling, you are outside. Open the visor, breathe in the pine wood air. Unlike a car where you're effectively disconnected from your surroundings, you're much more in them. You can also reach much more secluded places, so you can just go to "that spot" and spend the night there. It's almost as good as bicycles or hiking in that regard but unlike those two, you can also cover distances, spontaneously deciding to just hit the road for a day and sleep 1000 km further south the next night.
I live near the A7, a North/South directed highway in Germany going all the way from DK to AT and I also live near a motorcycle hotspot/meetup point.
In the summer, there are so many Scandinavians doing just that, making long distance travels with motorcycles, sometimes even with these small motorcycle trailers attached. They go camping in my town and continue the next day further south (or back up north respectively).
I don't have a bike nor do I like camping, but I love seeing these guys every time :D