Red shoes have a rich, symbolic history that harks back much further than Dorothy's glittering transcendent heels of ruby. Red shoes have been associated with power and prestige throughout history, so it is no wonder that an office like that of the Pope would deserve such a prestigious and showy pair of scarpe. How red shoes have always been considered a little trampy or risque for women is anyone's guess, mine would be something along the lines of power and prestige is not (allowed) for "nice ladies". Funny that red patent leather shoes were the first pair I actually threw a tantrum for while they glistened in a small town J.C. Penney's store. Given Italy's history of fashion, style and expertise in leather-work, the Papacy clearly earns some perks by being historically and geographically intertwined.
Papal clothing, or vestments, are taken seriously and this is another aspect that has a long standing. The clothing of the Pope and clergy of the Catholic Church in general was meant to inspire and conjure piety and religious fervor. The color red for the shoes, however, was adopted during the 16th century when all the other accessories were changed to white, except the accompanying cap and cape. Some of the most famous pieces of medieval clothing belonged to none other than Catholic clergy, the Syon cope for example, which is a delicate textile from c. 1300 - 1320 that was made in Great Britain and consists of linen entirely embroidered with silk thread, silver thread and silver-gilt thread, all the better for you to see in the dark, my dear. Some of this English embroidery work was so amazing and entrancing in candle light that the actual Pope in Rome is claimed to have requested an English cope of his own.
There is nothing quite like tradition. Just ask Fellini.