Maybe so,but the spoiler I installed had threaded brass inserts installed in the spoiler and was attached using 2 1/4" fasteners from the back side of the deck lid.While this might not have been a O.E. Honda part the fit was unbelievably good even out at the ends where it followed the contour of the deck lid perfectly(and less than half the price).I was almost convinced that the manufacturer of this spoiler was the supplier for Honda since the fit was so good,but since this one does "bolt" to the deck lid I now know it's not.
Almost never does an aftermarket part fit as good as O.E. but this spoiler is definitely the exception to the rule,even the paint was a perfect match.
Finding out now that the O.E. spoiler is only held on with double sided tape I actually feel like I bought the right one when I purchased the knock off.:smile as I pat myself on the back.
I thought for sure someone would post "what if I want to remove it and now have to deal with the holes",I can't think of ONE reason this would be the case but I guess if one found a REALLY cool WRX spoiler on Craigslist that one wanted to jury rig it in its place.
I agree with the sill plates staying in place only using double sided tape because they lay horizontal and come in contact with nothing(my feet haven't even come in contact with them) there is little chance they will move from their position even without using any type of fastener.
Good talk,
OMR