There are some reasons to be interested, given how expensive they are to make (in some genres), but overall I am always surprised how much we all seem to care h

There are some reasons to be interested, given how expensive they are to make (in some genres), but overall I am always surprised how much we all seem to care how much movies cost and earn. I don't ask that about books or musical recordings or even TV shows, yet somehow with movies I'm an investor?