Look at the entire design of Hide armor. Made of animal skins and furs and such. No other class would care for such armor.
Barbarian?
Barbarians can wear Medium armor without any restriction ...
The only armor that strips them from their Class abilities is Heavy.

And they look quite well in it. :3
I hear quite often that Barbarians are "not suppose to wear armor" ... but i dont think its true.
They more like just "dont neeed to wear armor" and only if their stats will support such build.

Sure, once you reach level 20 and get +4 to your Str and Con ... while your cap also raise to 24 ...
That is some SERIOUS competition for Medium Armors (
What would you need to wear anyway? 17AC? +2 Half-Plate? ... or even more if your Dex score is higher than 14, that sounds almost impossible to beat. 
) ... but thats something we both know (presume?) its not going to happen in this game.

(
Even tho i still think that we should get some "max level" bonus for pure classes. :P So quite honestly i would not mind at all if they would simply take theese bonuses and move them from level 20 to whatever level will be max.)
So, my point was that either restrict the class to certain armors or get rid of Hide. It's totally unnecessary in the game unless you restrict Druids.
Or they can simply boost its AC a little so it gets to same value as Scale Mail ...
That way Barbarians and Druids would get an alternative providing them the same protection as the armor they are wearing right now ... while fitting them much better both in immersion and style aspect.
