Is This a Bunker?

So Dustin Johnson would have been in a 3-way tie for the PGA Championship and played in the playoff holes that ensued. Instead, he was sent home as the first loser from yesterday's final round of the tourney. I guess rules are rules, but is this really the right way to see a PGA Championship end? I mean, I've played some golf in my day. And that isn't a bunker. That's a patch of dirt. If anyone ever told me I was penalized for grounding my club on that, I'd freak out. And I think in these circumstances, an official should be allowed to consult a player. Nobody would expect that it was technically a bunker -- it's the official's job to just say so. I think a fitting change to the "no-consulting" rule would be to make it the discretion of the official. If he feels it is appropriate to consult with a player about a rule, he should do it. Instead, nobody told Dustin Johnson until he finished the hole and headed for a playoff. Then they tell him that he's going to be penalized for that. Unbelievable. I don't particularly care who wins the PGA Championship, but I didn't think this was a fair ending for Dustin Johnson.