Having your wedding ceremony outdoors in, oh let's say, August? Much like Erin and Shayne did? Then you might want to do something else that Erin and Shayne did, and set up a sunglasses station for your super-squinty guests. These glasses could do double-duty as eyeball protection and wedding favors.
Bonus points for using a clever sign like: “Don't get BLINDED by our love. Please take some shades.”