Rich people who pester all their friends and co-workers for money so that they can bike 100 miles with a bunch of other people. Maybe one person doing this would not be a big deal but as I mentioned, the bay area oozes money from it's pores so at any given moment anywhere between 2 and 12 people who drive Maseratis will be asking me for a donation so they can go for a long bicycle ride.
Look. That's cool that you want to go for a long bike ride. I love bicycling. The charity? Absolutely deserving --- so just give them the damn money and enjoy your bike ride, alright?
Biking is not some weird sad chore.
Being fit and getting strong is good for you. I'm not going to pay you to do it, however.
Training for an event is terrific.
Going for a 100 mile bike ride is a lovely way to spend the day.
The charity rides I like are the ones where the bicyclist pays x dollars and then goes and does the ride and has a bunch of fun. The charity gets some money. The bicyclist gets a great ride and perhaps a nice tee shirt. Don't do this thing of "I am going to go for a giant long bike ride to raise money for $worthycause. You can help by sending money while I help by having a bunch of fun at your expense."
Important: not everyone I know does this. to those who donate some money to a cause important to them and then go bicycling? Stay awesome.