It's easy figuring out what one
should do, what is right. Mustering up the courage and strength to
actually do it- that isn't so easy.
as the hero, marcone for instance is the person to watch
Marcone can kill monsters, but that does not define a hero. He could not have found Lash's heart, or encouraged a panicking Butters, or comforted Kelly as Harry did- these actions matter too. Maybe more than the slaying, because it's
many heroes who will fight at Ragnarok- not just a single Chosen One*.
And at the end of the day, Marcone is still a parasite by choice. I don't think that getting magic Chosen One powers would change that- or that he deserves them on any moral, intellectual, or spiritual basis. It's not like there's one slot for a hero and Harry is occupying it, so Marcone
can't be one. It's that, knowingly and repeatedly, he made the choice to profit on the suffering of others. And if Harry were absent/evil/dead, Marcone would still make those choices.
It's not like they're fighting over who gets to sit on a particular chair.
* and the mercenaries who want his money