I will spend the money somewhere else and that is where they will be working in the future.
This is more like me buying from store A than from store B. Am I robbing store B?
Surely not giving to charity is worse than any other economic reallocation?
What do you mean by your first sentence? I am fairly sure that movies do actually cost quite a lot to produce.
That does not even matter since looking at marginal cost of a movie makes no sense. Do you want to see movies? If yes then pay for them, if no then simply don't watch them. Justifying stealing isn't the way to go.
I would guess that a lot of the jobs that are discussed in this thread are fairly specialised ones and if that industry would disappear they would be out of work.
That is an awful lot of time wasted of their lives.