2) All I can comment on is my own experience and perspective. They may or may not also represent developers in general. I’m sure that for every experience I draw from for these conversations, there’s probably a dev out there somewhere that will have had the opposite experience I have had.
This is an interesting question. At first I thought that the answer was simple: ‘the deleted and/or alternate scenes are complete for movies, while for games, the extra content is almost never complete before shipping the actual game’. But I realized that doesn’t necessarily ring true. For the deleted/alternate scenes in movies, maybe some post still needs to be done, or additional edits, or additional scoring or something.
Perhaps, and this is mere conjecture, it has to do more with how we interact with the two mediums. With movies we go to a theater, or rent it for our homes, and then watch it passively. When the movie’s over, the entire experience is considered done; complete. Especially in a theater, the movie tells the watchers when it’s over. At home with a special edition DVD, the movie’s still over, complete, fini even though the watcher can still choose options like ‘view with deleted scenes added in’ or ‘view alternate ending’.
When we get a game, we interact with it and it really only ends when the player decides so; whether that’s by rage quitting and breaking the disk, or finishing the end of the singleplayer story and ignoring multiplayer, or by falling out of love with the multiplayer, or something else.
Perhaps the interaction and choice has altered people’s perspectives because you’re right; there’s not much of a difference between deleted scenes/alternate endings in movies and extra content in games. At the same time, the extra content in movies is generally viewed as ‘complete’ before the movie releases. It’s extra finished content that’s cut before the release. In games it’s very rare to have ‘complete/finished’ content that doesn’t release with the game. With pre-order bonuses, of course the content is finished. But for DLC, it’s rare (in my personal experience) that DLC content is finished at the time of release. So DLC is rarely about ‘content that was cut from the original’ and more usually about ‘okay, we’ve finished the main game, let’s get to work on the DLC’. It’s conscious, purposeful additions to an already complete experience. Which is something movies rarely, if ever do.
So I think that movies and games have different definitions for what the ‘complete experience’ is, and since users have some authority over when their game ends vs when their movie ends, they feel like they have a say in how much they’re willing to spend to receive the ‘complete experience’ that they feel is owed to them by purchasing the game to begin with. But the player’s ‘complete experience’ definition and the developer’s, and the publisher’s might all be different. And therein some conflict can lie.