Can the venue admit with ID, e.g., if people forget the invitation at home? Guests will probably still be carrying ID, even if they forget the invite.
Are you having your wedding on a military base? If so I would say something like "The venue requires all guests to bring their invitation to gain entrance to the installation." I would put this at the bottom of your reception card. I would also put it on your wedding website if you have one and spread it via word of mouth.I would also be tempted to have extra copies of the invitation at the ceremony location just in case someone forgets theirs at home.