Please do not cut them.
Preventing them from racing all year may not be the best idea. You might hold them out of the time trial and the first meet so they don't race without having run/walked much and to let the weather cool off.
Our team has groups, varsity, JV and JV who "don't fit on the invitational bus". The 3rd group races the during the week meets. The time trial, 3 dual meets, an invitational on a random Wednesday and the county B meet. Maybe two of those require a bus ride. The varsity and 1st and 2nd JV, down to number 21 on the guys and girls teams get to run invitationals on the weekends. They run the during the week meets as three or four packs so they are more like tempo runs for most of the kids.
I would cut their warm up, maybe in half, and send them out on the day's run. They need to cover the same distance as everyone else. They can walk as much as they need to. Any kids who want to manage should also be encouraged to run/walk. One manager of my HS team 30+ years ago is still run/walking today which is a lot more than can be said for most of the varsity.