I apologize, I was being dismissive. I wasn't trying to say that weightlifting/bodybuilding/etc lacked meaning or were inferior, just that the motivations are different, and for me personally the intrinsic motivation of them (this muscle needs to be worked out, then this one, etc...) doesn't work as well for me as the extrinsic motivation (I'm going to finish this problem today) of climbing.
That's my point, though. The mentality of "this muscle needs to be worked, then this one..." is a bodybuilder mentality. It's not shared by strength athletes in powerlifting, Olympic lifting, strong man, and the much newer CrossFit. When I lift, I focus on movements, not muscle groups. I focus on big, compound movements like squats, deadlifts or clean and press, not on specific muscles.
Basically, bodybuilding is concerned with aesthetics, while the strength sports are concerned with performance. When I train, my motivation comes from the challenge. Can I deadlift 405 for 5 reps? Can I hit a new personal record of 435? It's a question of raw capability: what are the limits of what I can do? When you get into high rep rangs with compound movements, it becomes an issue of anaerobic endurance: can I squat 235 for 20 reps, or will the pain and exhaustion be too much?