I like flying because there is no damned good reason to do it.
I don't fly for transportation. I don't fly to test my skills (though I take training seriously and usually have something built into every flight that's on a training syllabus). I fly because it's fun, it's pretty, and it's all for me.
It's a random and unexpected sort of thing for one to do, and I'd say it's a guilty pleasure if it weren't for the fact that I'm completely shameless about it.