The bot is clearly crawling enough to be noticed, and consider the site: how much are you plagiarizing from videolan.org? If they're wasting even a small amount of resources, they're worth blocking.
reasonable
There are arguments on whether plagiarism is a bad thing in an academic context. I'm not nearly qualified enough to make them, but they exist if you want to go looking.
My homeworks aren't written to become public (they probably could because of their business)... I guess the schools are probably more to blame though.
it's not your homework that is public, but you may sourced text from the public
That company might leak and/or sell the data that they get from the schools?