discrimination against students

I recently had an interview scheduled with a nationally known company. The first question asked was if I was in college, I said yes, but that I haven't enrolled yet for fall and that I am very flexible and can take online classes. They refused to even continue with the interview stating that this company was not for me and that they don't hire students. I know this is a lie because I know students who work for the company. Is it illegal for a company to refuse to hire, or interview someone because they are in college?