Dawn, how many people does a rider need to crew, and what is the crew's function? Do you have a crew on all rides?
Most rides I don't have crew and it isn't an issue. Most 50 mile rides only have 2 holds and if the holds aren't in camp, you can generally send a bag out with ride management. That way I have all the stuff we need (water, hay, grain, elytes, a cooler, food for me, etc) and only need to ask someone for help when I run to the porta-potty.
However, a 100 mile ride generally has 5 (or more) holds. And in the case of the OD 100, all the holds are away from camp and in different places, so management does not take bags out for riders (just too much for them to deal with, can't blame them). This is where having a crew is a godsend.
Crew could be one person or multiple people. Having 2 makes the work easier and the time pass faster and can help with directions/navigation between holds. Crew carts all the crap Dream and I need during a hold from one place to another and then helps take care of her (and me) during the holds. It's a fun but very tiring and often challenging ordeal. I have helped crew a couple 100 mile rides and honestly, crewing is as hard if not harder than riding the 100 miles! Hopefully this
will link you to a bunch of pictures I took while crewing the Vermont 100 for a friend.