I sent out invitations and save the dates, but everyone was invited verbally first, and we knew already they were all coming. I did the invites and save the dates for me mostly, my mom's making a wedding scrapbook, and you can't have that without the invitation right. I think it's really up to you what you do. If you want to take the time and money to do them go for it, but if it's not important to you then just go with a verbal invite or a little note card with a simple note inside.
Melissa