I read a lot and now I need glasses. Is that bad?

Probably age. Reading is one of the best ways to get information and be entertained. The use of near vision does not alter the basic internal structure or focusing of the eyes. As you age (over 40) your near vision may need help as your natural lens hardens and loses its near focus. That is why stores have racks of reading glasses. This is a natural progression and not due to your reading.