(This question seems like it ties in somewhat to the thread about regatta insurance to cover race committee for liability.)
As fleets get smaller, they not only have fewer sailors -- they also have a smaller pool to draw from for serving on race committee. When a fleet hosts a regatta, most of the active sailors want to race, not raise flags and drive powerboats.
Is it getting to the point where we have to patrol the local drinking establishments and shanghai people off barstools at closing time and let them wake up on a race committee boat too far from shore for them to escape?
And where do you find enough power boats -- and drivers -- to serve as mark boats? 
Mary,
we have found that reciprocating with another class or fleet really benefits everyone. Last year we recirpocated RC duties with the local Thistle Fleet. They supplied the PRO, we did all the work. We worked under the insurance realm of the Local sailing clubs insurance, whom we used their Boats and facilties. The Thistle fleet was sanctioned as an official fleet of the club and to my understanding fell under the insurance plan as well.
This year for our Tommy Whiteside Memorial/SuperCat 20 Championship regatta we are reciprocating RC duties with a Monohull Club(Lake Murray Yacht Racing Association) which has their own insurance plan, and we are also covering ourselves as being an officially sanctioned event of the Columbia Sailing Club. We are using their facilities and boats, and fall under their insurance plan also. Incidentally we also have to apply for a regatta permit from the S. Carolina DNR, something we have never had to do before.
Point is, find another fleet, yes even unihullers to exchange RC duties with. You both win.
David Mosley
www.seacats.org
For our regular Tuesday night races, we only recently came into having regular committee to run starts and keep times again. Before that we agreed on course on shore, one boat would volunteer to run the starting sequence on the water, and we'd all keep our own times. We certainly did not want to have a team on shore when they should be sailing! We use nav marks and semi-permanent marks set out by the local keel boat fleet, and pick a course around those based on prevailing conditions. When we've wanted to set our own mark one of the sailors would drag it out behind his boat and set it on the way to the start. Honesty and sportsmanship are required for tis approach...
Now at least, we've reached enough critical mass to have folks who enjoy coming out and helping with the starts and time-keeping. But that is done from shore on the Pirates Cove pier - we always have the same starting line. We have no committee or crash boats, sailors know that they are on their own. Because of all this, our races come off as kind of cross between windward-leeward and distance races. Our starting line is never square to the wind, sometimes we start downwind, somtimes upwind, etc. etc. etc. But it seems to work.
The few invitationals we've done aren't that much different, except we defintely try to have committee!