The 2003 movie thimble

Why does everyone seem to think Wendy and Peter "thimbling" at the end of the movie is so wrong? In the book they thimble in the nursery in chapter 3...the play is another story however...as in that one it seems almost as if Peter really is a boy who has died. There are some differences between play and novel. But in the novel..they do thimble....to me it's just moved to a different part of the story *shrug* Mrs. Darling's kiss just means something totally different in the book. I like how in the movie they say the hidden kiss is seen on Wendy's mouth. And I'm also a believer that children CAN fall in love so I really like the movie version. My boyfriend is pretty sure he's heard somewhere that Barrie wanted people to expand on the story and universe so more power to the creators of the 2003 film.