I was thinking of this post yesterday, and I don't think it goes for just our hobby.
Case in point, I am an avid cyclist, and my bike cost over $5K. One of my friends who is big golfer found this fact out and was floored. He couldn't believe I would spend so much on a bicycle.
When I asked him how much his golf clubs cost he immediately replied $4,500. I then reminded him I didn't have to pay greens fees to ride, nor take trips to golf courses for my hobby and he saw the point.
What I am saying is I don't think you ever truly can explain you passion for any hobby to those with dissimilar interests, though pointing out Joe's golf expenses did stop him from picking on my bikes!!!