Traditionally, the rehearsal dinner is not just for the wedding party and parents of bride/groom, but also for any out of town guests (or so I've heard). Most of fi's and my guests will be coming from out of town, and that puts the rehearsal dinner guest list to 87; this just does not seem realistic.
Is it ok to limit the rehearsal dinner to just parents and members of the wedding party? Or will that be a huge wedding faux pas?