I guess that's the best answer. Obsessiveness is a mental disorder though, and it strikes me as similar to walking up to someone and starting off with "what are your addictions" or "what are your compulsions" as an ice breaker, which would generally be inappropriate.

Even taking it most charitably it presumes that most people are obsessed with something. I'm not, I'm not really passionate about anything either, certainly not anything I do professionally.

The last time I was at a conference, if anyone asked me why I was there my honest answer would be "my boss said I should go" and if they asked what I had enjoyed the most so far my answer would be "I skipped all the sessions yesterday afternoon and went to a gym and lifted weights for two hours." If that led to a conversation about weightlifting, I wouldn't have much to say. I don't obsess about it, I don't have a coach, I don't compete, I don't know any names of professional lifters or their latest records, it's just exercise that I do.

I guess it boils down to, I'm a pretty boring person. I generally feel like I don't have much to add to a conversation and it's uncomfortable to answer questions that reveal that. So I do generally try to keep people talking about themselves, which most people seem happy to do.