The only reason he gets stick is that he seems to lack fundamental footballing skills. I find his goal record baffling when I see him play sometimes but, personally, I don't give a crap what his first touch is like or what he says to the media as long as he sticks it in the back of the net for us.
It's exactly this. When he went through a dry patch recently, he was such a liability that even Arouna Kone felt like a massive upgrade when he was on the pitch, as when Lukaku isn't scoring we may as well be playing with ten men.
If you use Lukaku as a focal point striker and put five chances on a plate for him a game, he'll convert more of them than your average striker will. But that really isn't enough for a top tier team that relies on a cohesive team unit to play at our best. Lukaku is often the weakest link in our side, more often than he is the strongest link when he's scoring.