The definition of regional caps is a difficult one.
This varies considerably depending on the country and the systems operated within it.
It can also differ considerably within a country depending on the period in history. As the game has developed and changed, so have the team structures, divisions, tournaments and trophies played for within it.
On the country specific page I will try to add some detail about the system operated within that country to the best of my knowledge, which should allow you to understand why these caps have been included in that specific page.