Why dont we see black movies heroes?

I have watched Superman, Batman, Spiderman, 007, Indiana Jones, Transformers...and many more.... and have wondered why I have never seen one single movie where the hero was a black man. Aren't there some black folks out there that could've done a better job if offered a role? Why can't producers think of them? Do the movie producers underestimate black people, and refuse to include them entirely in a mega million production? Do they think they will screw up and fear that the movie won't generate an income when it's released? I really don't know why.