Short Cuts, I Think Not!

Ok tv is starting to annoy me. Or more specifically premiering movies here in the UK once they reach tv.
What is it with the need to cut things out?

This Friday just gone Thor premiered on sky for the first time. Now I saw Thor back last year when I was in the states and I saw it at least 3 maybe 4 times so I know there are at least two scenes missing from the movie.
1. Being Thor and Erik singing
2. Thor replacing a mug in the cafe

Sure these scenes aren't entirely important, but they are part of the whole story, one ties up a loose end with Thor's own character but it completely throws out the beginning of the scene that they left in there of him making breakfast, and the other is bonding/acceptance between characters.

So what if this were a book? This reminds me of the whole "it was Dobby not Neville!" instance in the Harry Potter and the Goblet of Fire book and movie, when Dobby was completely dropped as a character in the movies before returning at the very end of the series, what was the point in that other than to simply please the fans after annoying them for what 3 movies and then still have Dobby die. Was it to please fans? or simply to put Dobby to rest? Or because no-one else could get Harry out of that house? if it was the latter then I hope the makers were kicking themselves afterwards because Dobby was a mass loved character and should have been in those previous movies.

I hate these instances, they're annoying! If it is in the book and it is part of the story then it dont need changing! If we all took shortcuts nothing would be done properly. If we took shortcuts in writing, the stories would never be complete.
Is it really so difficult to just leave things be!?