Larry Bong 说:
A tavern, have u ever seen a castle without a tavern?
First of all, castle itself is a noble's house. Not a tavern or marketplace!
Also castle is a military object with restricted access.
Of course, it must have the supply stores with food and ammunition, also stables.
But without any sizeable commerce or craft facilities!
I don't think that any kind of mixing of castles and towns into one class will be correct.
A caste that implemented with shops, tavern, etc better to be called a town.
Regardless of its size or presence of outer fortification.