Phallic Symbolism is fucking EVERYWHERE. Do you doubt? Look around you--can you spot at least five penises in your general vicinity?
The phallus is an ancient symbol of virility, fertility, and Patriarchal Power (thanks, Dan Brown! That one was tough!). It's also inescapable. Architects, artists, and religious leaders are always sticking it in places where you least suspect it (heh. Get it?).
For more on how Masons, realtors, and the like are subliminally seducing you to the dark side: