There was a time when the mask business in Venice was more than just a quirky feature of the tourist trade. No one really knows if the original intent was political (for anonymous voting) or social (to disguise your class and identity). But by the 12th century, both the wearing of masks and the behavior of the male wearer (no women allowed) were highly regulated—no gambling, no weapons, no throwing of rotten eggs, no lurking around the convent to seduce the novitiates. Eventually, the practice became entwined with la Carnevale di Venezia—a cross between an orgy and a political riot—so when the prudish Austrians took over in 1797, they banned both.
In 1979, both mask and la Carnevale returned, albeit in a more tourist-friendly and gender-neutral mode. Most of the masks available today are modern inventions. The Volta in the photo (feminine, ghost-like, and covering the entire face) is the most popular and least practical (no eating or drinking). The glummer male Bauta can come with the mouth hinged or unhinged, but it does leave the wearer looking a little formidable. The masks with the long, hideous noses, the medici della peste, were originally developed for the safety of plague doctors, but are worn today by anyone with a taste for Freud, ostentation, and the macabre.
Like most such traditions, la Carnevale has been swamped by the tourist trade, with over 3 million visitors a year showing up every spring to misbehave. And before you decide to buy a mask, you might want to check the origin. If you can afford it, it was probably made in China.