I hate info controls that are there for no good reason. One ACP 200k I have ridden has a control every 10 miles in the second half and you only need the finish.
There is an obsession with proof of passage in the U.S., dunno why. PBP has a control or stop every 100km, because most riders need those stops.
I have designed at least one 300k perm, but never got it approved. Realistically, I was never going to ride it and nobody else would either.