IMO, I think he made it out of curiosity 'cause every people are curious if there are many people risking in gambling to gain profit or is it just for fun only. It's normal to ask some complex situations like this 'cause it's hard to tell whether the people are just enjoying gambling or being serious to get money on it.
I just imagine my wife ask me: "Pandu why are you gambling?"
WTF, she never knows I'm betting at football. And of course, I can't find the right answer to the question.
Should I answer the questions with this?
1. Enjoying
2. I love
3. Hope for a win
4. Fun