Huck is like that hippie kid with questionable hygiene who can't stop talking about how he once hiked the Appalachian Trail. No walls, houses, beds, and chairs for this guy; he'd rather be living in filth down by the river and chilling with the squirrels. But to put a positive spin on it, Huck does turn out to be the only character in Huckleberry Finn who's able to make the right moral decision. Maybe there is something to be said for all that communing with nature.
Huck may like being outside, but in the end he prefers the civilized world of family and home.
Although he doesn't mind the civilized world when he's there, Huck really belongs outdoors on the river.