My grandfather was an airplane nut (flew for RAF in BoB, and was a flight instructor at least part-time for the rest of his days) - he built lots of models, and real planes as well. I grew up building both with him, or at least 'helping' in his shop. Building kits is a blast, but so is building a 1:1 scale airplane! No one can tell you you need more of a detail wash on your instrument panel!
I got away from it for a while in high school/college, but soon after, came across a hobby store and saw some kits, thought about how much fun it would be to build one again, and have been hooked again ever since. Its just great stress relief, even to sit down and get lost in a kit for only 1/2 an hour. Now I build some aircraft, some trains, but mostly armor lately.
Jeff