A silver sixpence in her shoe?

So I've been researching the history of various wedding traditions, partly because I was interested, but mostly because I was bored at work Anyway, to my surprise, the poem "Something old, something new, something borrowed, something blue'" ends with the line "A silver sixpence in her shoe." I had never heard that and was just curious to see how many of you did the something old something new, and how many actually did the sixpence as well? Is it uncomfortable in your shoe? ( I just imagine dancing all night with a pebble in shoe!) I found a New Zeland sixpence for a few cents on ebay, so snatched it up, but curious to see what you all thought about that particular tradition.