OK sensible answer (for a change)
In origin it is believed that the idea was to permit, in more restricted social times, party goers to act in a manner that they would not otherwise have done had their identity been known.
Many cultures still celebrate this. In parts of Germany, where I was privileged to serve, there is one night of the year when a lady may pick any man of her choosing and indulge with abandon as her fancy takes her. Known in English as "Rose Night" (Rosen Nacht) or Rose Monday (Rosen Montag) this is a day of feasting, beer drinking etc. The ladies are costumed but the men wear normal clothing and ties. The ladies all carry a pair of scissors and they will select their target and snip off his tie (the symbolism is obvious even to those on this forum). As the evening festivities wind down the fun begins as the still costumed and masked ladies claim their mate by matching the piece of tie they hold. Etiquette demands that no gentleman can refuse the lady holding his tie nor may he unmask her. Certainly this was still going on the the sixties and seventies when I was there.
So now you know.
