Wine cork escort card holders??

my fiance and i made our own wine cork escort card holders and i have a little question... should we just sit the cards in the holders or should we put a little bit of glue in the slots so that the cards can't be removed?

a few of my friends said they would be inclined tojust take their card and leave the cork, so i wanted to get some opinions on it.

here's what it will look like...

I would just sit them in, what if some people do wanna take them?

I was totally going to do this, until I learned my RH does my cards for me, so I didn't want to spend the money if it wasn't necessary. Great Idea! :)

we did the same thing (no glue) and everyone took the corks with them. I think people will get the idea