I've heard about the existence of the full volume, but to date I don't think I've ever seen nor laid hands on it (if I've seen it, I think I would have remembered browsing it). I have a feeling that most people who speak English as their primary language won't even be aware of its existence.

The Encyclopædia Britannica is the only thing I've (slightly) leafed through before I started really getting online. I remember its thin pages and dry reading compared to less formal encyclopedias. I even remember pining over advertisements of the CD/DVD set and thinking about whether it'd be better to connect to the internet at home, or get the DVD of Britannica.