I railfan for many reasons:
1. Have an excuse to be outside
2. Explore, visit new towns and learn about history of new towns
3. Public policy and regional planning interest. Whenever I watch an intermodal train roll by, I wonder: What is in those containers? Where were the products made? Who made them?
4. Surprises. I love watching trains go, watching for messages from people I don't know, like this one: