You're not retarded are you? If so I can type slowly.
Why do you assume the powerlifter, karate guy, and yoga student aren't the same person? Folks aren't so one dimensional that their lives can be summed up with a single word description of one hobby.
Yoga is great for:
1. Judoka, BJJers, and really any martial artist that wants to maintain flexibility and balance
2. Field sobriety tests. Honestly Yoga and Tai Chi make passing field sobriety tests a breeze no mater how drunk I get.
3. Dan John said yoga was awesome, and has mentioned it in at least three of his articles. Are you calling Dan John a liar? Are you?!?!
4. Women. Crossfit and Yoga make women hawt.
5. An incredibly demanding workout. There's a reason why the Yoga DVD is the most hated DVD in the P90X workout series. The stretching and balancing, forward and backwards rolls, and some tough transitions from pose to pose will get one's heart racing while a pool of sweat begins to spread across the floor.
6. I had a horse named Yoga. He was fast. I mean really fucking fast. He was a retired race horse, so it was expected of him to be fast. He was pretty awesome. A retarded asshole at times, but mostly awesome when not being a retarded asshole.