I didn't read encyclopedias, my addiction was the big National Geographic Atlas of the World that my mum owned. I loved looking through that thing - I still love maps. My sister credits my first desire to move to Canada to the time when I read the population density statistics in the atlas
I grew up in a sci-fi household though, so that was normal for me. I remember trying to impress my dad with my reading and saying "I'm reading books by Harry Harrison, have you ever read any of his?" - his reply being "read him? I've met him."