I then did a little research on them and their origins, etc, etc (a nice Wikipedia read as all "research" is these days) and stumbled THIS little gem of an article. It's an article in 2007 (before the Union were a team) by an English reporter on the grassroots soccer fan movement in the US. Here's an excerpt:
...the Sons of Ben... are fans of Philly's Major League Soccer team. But Philadelphia doesn't yet have an MLS team. Which is to say that, despite having scarves, songs, chants, replica shirts and flags, they're fans of a team that doesn't yet exist. It's almost as if - in the manner of the South Sea cargo cultists - they're trying to will a Philly team into existence. They even organise trips to New York Red Bulls games, just so they can boo them. How hardcore is that?...Brilliant![to the Top of the Blog!]
...Sons of Ben are following in the noisy, irreverent, chaotic footsteps of the Chivas Legion Kalifas (Chivas USA), the Galaxians and Riot Squad (both LA Galaxy), Screaming Eagles and La Barra Brava (both DC United), Empire Supporters Club and Raging Bull Nation (both New York Red Bulls), and Section 8 Chicago (Chicago Fire). And, of course, the national team's Uncle Sam's Army who chanted, at a friendly against England: "We've got dentists!"