Good advice Chilla.
No-name, the fact of the matter is, no one can tell you why to train. No one gets to be your moral judge but you. If the instructors at the Krav school are reluctant to teach you, then explain things to them and be confident when you do. Tell them what you've done to try and resolve things peacefully, and tell them that the reason you came to them is because you need to tools to be able to handle things if peaceful resolution fails. You seem fully capable of avoiding conflicts, and therefore you probably don't need their help staying out of fights. What you need is for them to teach you what to do when violence is the only option.
A lot of martial arts instructors feel this Karate Kid need to act as some kind of spiritual or moral guide to their students. That's a fine thing, if it's what the students need or want. But when you're there to learn to fight, they ought to teach that first and save their moral judgements for personal time and conversations.
Let them know what you need. Tell them why, and show them that you're taking steps to handle things legally and peacefully. But also let them know you don't think those measures are enough, and that your only other recourse is to follow the advice of some guy on line who keeps telling you to poison their drinks and blast them in the back of the neck with a 2x4 when they aren't looking.
