I believe more suggestions and less criticism/complains (definitely no attacks each other) should be encouraged for non-profit activities, either for organizer or participants. We, the Chinese fellows, should be proud of our organization and supportive to our activities.
It is true that cost for the activities has to be covered by the activities themselves and participants should cover their own expenses in general. However, as an immigrant, we all experienced the difficult time period when arriving this new place. Helping each other does not have to be money involved. Purpose for a day tour is to have fun, know each other, and meet friends. If one of the organizing committee members can coordinate the car pool issue by registering persons who have cars and those who do not, most probably, transportation should not be a problem.