DF and I have found invitations that we like on Minted. We're trying to save a little money here and there where we can, and one option I'm considering is printing info on the back of the invitations instead of including an extra insert. This would save us $150 on the inserts themselves, plus about $20-25 on postage (because with just the invite and the RSVP card, we could use standard stamps, but with another insert card we'd be over 1 oz). The info would be the rooms that the ceremony and reception are in (our venue may have another wedding on our date in a different room), the phone number, website, and discount code for our hotel room block, and our wedding website address.
Would it be weird to have info on the back of the invite? Would people even look there, or would they just miss it? Obviously if no one would look at the back of the invite, it's pointless to have the info there at all and I'd rather pay extra for something that people will actually read/will not side-eye.