Probably with the intent of you throwing it on the old original Joker that had the bad sculpt. Take off the jacket, and have at it. Personally, I love the way the slick back hair version looks (by the way, is the cop version minus the makeup the same sculpt? Probably a super dumb question) on my BR Joker. Granted, we didn't really see him exactly like that (hair wise), but we can use our imaginations a little bit.
I also think some go a little overboard about inaccuracies, therefore fueling the fire for Hot Toys to just crank out an even "more accurate" version. I'm starting to think that they are doing that on purpose. Not initially, but recently, yes.
No. RB sculpt has more of a grinning smirk and his hair curls up slightly in the back at the base of the neck. Police has a more devious expression. Great figure by the way that doesnt get enough attention.