I'm designing my invitations on Vistaprint and I'm wondering if it would be odd to put details card like information on the back of the main invitation. It's currently just a blank space. The ceremony and reception are in the same place, so all that needs to go on an enclosure card is the hotel block and our website, I guess (unless there's other info I am missing). I would love to save paper, and I am doing a separate RSVP card, I'm sure etiquette would say it's a no-no, but has anyone else done this?