"Last Activity" types for Clubs

I am signed up for several clubs. When I choose to look at all my clubs, I can see when the last activity date was, then I look at those clubs that have had the most recent activity. Most of the time, that "latest activity" was apparently someone joining or un-joining the club, since there are no new comments/posts/pix/etc showing the same "latest activity" date as was previously shown.

Is there a way to modify what the system thinks is activity, so it doesn't include when someone joins or un-joins a club?