St. Peter's Square is a Judaic Merchants' Square

... Of the existing 113 licenses that allow souvenir selling in Rome, 112 belong to Jewish vendors.

The profession dates back to the pontificate of Paul IV (1555-1559).

While confining the Jews to the Rome ghetto, the pontiff allowed them to exercise minor street trades.

When Italy unified in 1870 at the expenses of the Pope’s temporal power on Rome, Jews turned into souvenir sellers after obtaining ad hoc licenses from the Italian civil authorities, while some were granted such right directly from the Vatican authorities.

The "urtisti" – literally those who bump into the tourists -, deal in small plaster statues, crucifixes, rosaries and pictures of saints and Popes still nowadays.

Until December 2007, the Jewish sellers were allowed to work on the entire territory of Rome, and part of them directly on St Peter’s Square ... (Daniel Mosseri, "Rome's Jewish vendors of souvenirs protest against their expulsion from Vatican," European Jewish Press, Jan. 18, 2008)

http://www.ejpress.org/article/23279