Others. Why? (Marvel's Avengers)

Hello. Maybe a stupid question, but still ask. I'm used to individuals of the original marvel heroes, enjoy watching the franchise, several times reviewed the War of infinity and the Final. But damn! The game is another person. Why?

Tony stark should be the face of Robert Downey Jr., and Captain face Chris Evans, etc. But in the game they are very different!!! And it spoils the impression. Seems like a cheap Amateur fan-made. Why? Money is not given on the star cast?