White bucks are a traditional summer shoe that have had a resurgence in popularity thanks to menswear's general tendency to look backward for inspiration in the present. I don't think I could see myself wearing them (I have gray bucks with red soles, which are more suited to the way I dress), but they do have an undeniable old-school panache that works well with warmer-weather clothing.
Yesterday I was doing some errands at a strip mall near home. There is a shoe store there that I don't generally pay any attention to, but I happened to be walking past it to get from one store to another and decided to go in and have a quick look around. I spotted a pair of Bass white bucks with red shoelaces instead of the usual white ones. I had no interest in buying them, but I thought this was a clever way to make a fairly plain-looking shoe more interesting, particularly since the red laces were intended to play off the shoes' red rubber soles.
It occurs to me that for someone who already owns white bucks, this would be a very easy and inexpensive way to give one's shoes a more distinctive look, and you wouldn't necessarily have to go with red for the laces. Colored laces are now available in a rainbow of colors for as little as $3 a pair if you do a little searching online, but don't pay more than $5 or so; that's just a ripoff and not worth it. (I think Allen Edmonds has them on their website and possibly in their stores as well.)
If you really wanted to get carried away, you could swap the laces the way some people swap out their nylon watch straps depending on what else they are wearing on a given day. At the very least, it would add a small touch of coordination to a summer wedding outfit.