They are to make something very clear to us: we are not heroes, we are adventurers. Yes we do cool and awesome stuff, but we are not Thrall or Jaina or Grom. We're maybe Garona. Our names aren't really known. Oh sure we get a letter of recommendation here and there, but in general, we're just anonymous people waiting to be hired just for something to do.
The only group that I've seen really notice us was the Scourge.