It is definately a possibility. I have been on several cruises where a disclaimer has been signed excusing the club and organisers of the cruise from liability. However keep in mind that contractual agreements of this kind are not binding at all.
Basically in the event of something going wrong; this usually occurs when the road rules and laws are not obeyed, which in turn throws out any use of a disclaimer. As such, liability would fall behest to the parties partaking in the illegal conduct, ie individuals. However if a person was participating in a cruise, where illegal road behaviour was encouraged eg drag racing, drifting etc, the organisers in addition to individual members would be held liable. Not only the organisers, if the club becomes fiscally an entity, or a corporation, the club itself can be liable.
Basic safeguards include a no tolerance policy on illegal behaviour, which includes public dissavowing of poor and dangerous driving to enforce the club's stance on dangerous behaviour, setting a precendent and distancing the club from the idiotic acts of individuals, and of course, public liability insurance which is not a viable alternative due to financial reasons, but the best nonetheless.
I am sure Prank's old man could shed some light on the issue, as can other members in the legal profession. I am doing contracts law next semester, so until then...
Pete.