LSRCC in Duluth, MN is roughly 48x100. Bigger events potential is 60x120. I couldn't imagine only 4 marshalls. EVERY driver marshalls (or is supposed to) regardless of track size.
If a marshall goes left to assist a car and then to the right on another part of the track in that particular marshall's 'zone', does that driver have to wait?
If two marshalls face back to back, (doubling up) then both opposing directions are covered.
I can't see how the marshalls can be in the way of the drivers' line of sight if they are positioned on the perimeter.
Even the race directors at the tracks I race at do their turn at marshalling.
Hard and Cold, maybe so: Marshall, Get DQ'd or GO HOME.
Not marshalling is disrespectful.