I have to be very careful about talking about why the subreddit even exists or we get slapped for brigading; Reddit is staunchly against anyone constructively criticizing subreddits/moderators.

And only you as a mod needs to be that careful. The users will keep going to r/tampa and antagonizing r/FreeTampa, or the opposite, as there is no rule that directly forbids regular users from doing it, only the one directed to moderators.