I've personally helped organize and run a couple of these for the Fraternal Order of Eagles in Carlisle and I can tell you we give 100% of the profits to our charity. We get local businesses to donate door prizes, the Eagles supply the meal at the end (nothing fancy; hot dogs, beans, chips, etc,) labor is all volunteers, and we host it at our picnic grounds.
We have had over 240 entrants each year and have yet to pick a day with good weather. (Go figure.) The riders usually leave in groups of various sizes and receive one card at each of four stops along the way. The fifth card is selected back at the picnic grounds and the best poker hand wins.
We have raised thousands of dollars for cancer and diabetes and, as always, "A great time was had by all."
We also do 50/50 drawings, an auction, etc to "boost" the monies given to charity.
The ride generally covers 125 miles or so.
If you get a chance, get a couple of guys together and join the fun. You will not regret it.