Yes, random guys may have beard. But is there any national team in the world (let alone in the WC) in which 90-95% of the players have beard?
Having beard may be in style these days, but as usual Iranians just have to take it to another level!
BTW, I agree with Dr. Strangemoosh about Jahanbakhsh's beard. As long as it's trimmed and well-kept, it's rather nice. but even then, not when the whole team have it. It's enough with 1 or 2 players.