Does anyone know why...

[EZLN]

The Indonesians use the term "Pers" so much in their footall club names? just look at the names of the teams in their super league

http://en.wikipedia.org/wiki/Indonesia_Super_League

[K.C.I.N.]

it's even in their words like this
e.g.
persahabatan - friendship
persaingan - competition

[maniei]

maybe its the equivalent to the latin "com-"

[EZLN]

but they have a team named Persija