I kinda understand your point, but it's not hard to see how it happens. There's other "top prospect" players that go after him. When you're putting a team together, I can definitely put at least 4 guys names before Harper that I would want on my team...especially considering the plethora of OF talent in the big leagues.
I know everyone expects him to be a no doubt awesome player, but he's still young, and could possibly (probably not in this game) decline.
I personally don't think it's that big of a deal, but to each their own.