How have you planned to accommodate guests that did not respond to the RSVP but still show up? I have reached out to several people who I have not heard from and never received a reply back. We are having assigned seating. Do we add a few tables in the back? I even pre-stamped the RSVP card envelopes to make it convenient for people to just reply and toss it in the mailbox... but you know, that can be too difficult too.