Ok if you are this I think is the reason.
It started when all the
Highland League teams who were constantly hammering 3rd, 2nd, and even some 1st division clubs in the cups< ( that was my semi colon) and getting bigger crouds, better finance and generally left out of the SFA professional scene.
So when the SFA decided to enlarge the league they looked for new clubs to fill the spaces.
There is a similiar situation in central Scotland, where Junior teams often beat League teams in the Cup. Gala Fairydean being one that springs to mind. In the end they chose the Highland teams for the reasons Mentioned above.
I hope that clears a few things or else I got a sore wrist for no personal pleasure