[Desafinado]

I did see one a long time ago but there's no way I can find it now. Basically it said that wealthy people read significantly more than poor people.

It's not that difficult to understand. For example, my kids go to a low income school where many families are having a hard time feeding their kids consistently. How many books do you think they're buying? Maybe some, but a hell of a lot less than my wife and I are.

Reading itself also takes effort and energy. If you barely have food to eat then reading isn't an appealing activity, most of the time.

Many families fall under this category.