To my mind, it isn't. Learning how to deal with and even commit violence does not mean one is personally violent or likes violence. We don't expect someone who has trained in CPR to like heart attacks. Heart attacks, like violence, happen whether we want them to or not. It's best to be prepared.
Also, while I dislike violence, I hate cruelty and evil even more. Have you ever been in a situation where someone was being victimized and you were unable to do anything about it? I was, as a child. A friend's mother was giving me a ride home early one evening. We drove past a parking lot where I clearly saw an elderly woman being attacked by a gang of teenagers. I told my friend's mom what I had seen and asked her to pullover and call the police. She refused, saying I didn't really see what I thought I saw. That happened over 30 years ago, but I still remember it vividly.
I respect and honor life. That is why I stopped eating meat. It's also why I'm a martial artist. I practice hurting people because I cannot stand seeing people get hurt.