Philatelists (stamp collectors) are still around, although email has pretty much wiped out snail mail.
Numismatists will also be around, when Bitcoin is dominant. I don't see fiat getting wiped out.
It's already a very small industry, and a sudden shift to digital currency, could destroy it. As a young kid, I was a active collector of old coins and I enjoyed collecting foreign currency too.
I still have most of my collection, but almost all my friends stopped collecting at a early stage. {The boyfriend/girlfriend stage.. and then husband/wife stage}
I am saying, it would be sad, to see such a interresting industry, fade away into obscurity.
![Sad](https://bitcointalk.org/Smileys/default/sad.gif)
Numismatics are more popular than ever. The hobby is more active than ever in history. It is collecting art and history at the same time. I can't see this growing trend and popularity of coin collecting plateauing, much less decreasing, given the world population is increasing faster than ever.
Rare, unique, and mint state coins will continue setting records in their desirability and monetary value for centuries to come.