Help Ma Understand Sceduled Maintenance

I've never had a new vehicle before. I took my truck in for service, and was talking to one of the guys at the dealership. We were going through the scheduled maintenance list, and he said of all the things listed, the only one I HAD to have done to keep my warranty was the oil change. Is this true? I know I don't need the dealership to do it, but what about all the other crap on the schedule (ie: cabin air filter replaced, brake service, tighten propeller shaft?)