The tradition of tossing the garter originates back to the 14th century, where it was believed that grabbing a piece of the bride's dress would bring good luck. Some rowdy guests would inevitably start ripping the brides's dress, and so to prevent that from happening, brides began the tradition of throwing pieces of their dress to their guests - the garter being an item tossed to the males.
Some wedding traditions, like uncomfortable speeches and over-inebriated guests, should be celebrated because they are usually hilarious and memorable. But some traditions (receiving lines, wearing something old?) should be looked at more closely, because who really wants to participate in the garter celebration? Anyone? I didn't think so.