It's almost a thing of the past now and very few people must be using it. For those who must be having it may not be using it and must be only for show purpose. I have retained one for my own collection. For the new generation the dictionary is an online thing. They do know about dictionary but for them the reference is different. I am sure in the next 10 - 20 years it will be completely outdated. The same will apply for encyclopedias also. Telephone directories are already obsolete, they do not exist any more, though I am sure some people may be holding it but they may not be relevant any more.
Probably in 50 years these will be things in museum, like how we are already seeing things of 30 - 40 years old in museums like the lanterns, the old gas -stoves, some cameras and video recorders and many such things. In my school days, we did not have mobile phones, they were not in existence and this was one of the most important books for us. I used it all throughout my schooling. I was supposed to carry the dictionary to school every day that was our teachers instructions.
I remember my English teacher would make us spend 10 minutes of her class on reading the dictionary. We had to go through 2 pages and understand each word's meaning. It was a very good habit that she had developed for us, it did help a lot in developing my vocabulary. When my son was in school, I followed the same practice for him. I could not do it every day but twice in a week we would sit together and go through couple of pages understanding each word.
These were powerful techniques of improving the brain capacity and IQ level. Now also there are systems but they are different and they are all technology driven and instant where you may not have to put too much brains. If you want meaning of a word, you can enter on google and you get the answer, but with the dictionary, you have to turn pages and find your word, which needs some mental work and it is not instant.
We do move ahead with times but then these are some sweet memories of my school days and I cherish them a lot.