I don't bring any tools to the hill!
Been snowboarding 20 years and only NEEDED tools at the hill once or twice. The on site shop always has tools you can use.
For what it's worth, when I setup my boards I tighten the binding screws down with a cordless drill. I set the chuck to a firm tension that isn't hard enough to start pulling the inserts, but firm enough to ensure they don't back off. Plus most hardware is pre-treated with threadlock. Install it right once and you shouldn't need to keep tightening. I check mine about every 10 trips to the hill just to be sure.