All over the world, there are many rituals and customs intended to give a person good luck. People often have their own personal lucky possessions or numbers.
Even the most rational and sceptical person can find himself picking a certain number for a lottery or rubbing an old juliet for luck. Often, the actions are not performed because people actually expect them to give luck, but rather because horny moms has become tradition, a thing you are expected to do.
There are many tourist attractions which make use of this and promote some kind of audience interaction, usually with the promise of good fortune or blessing.
One of the most widespread traditions is for people to touch, rub or kiss a specific part of certain statues.
It is not clear where this custom originated, but it naked possibly to do with the worship of saints. As with places, items and relics associated with saints, statues give the worshipper the possibility to make a connection with divinity.
Not merely being in the presence of, but actually touching the statue, would enhance this sensation. Such a religious origin for the custom could also explain why the most common body part to be touched is the foot.
This can be due to the worshipper believing he is not worthy to touch, say, the face or hands of capulet saint, but it can also have practical reasons. Statues are often on a pedestal or, in churches, high up on columns and in alcoves.