That's exactly what it is, And I know Kokomo and Paragon also held KISS style races and purses even after the series stopped.

It was a series for weekend racers to visit other tracks and compete against each other for te title of King of Indiana. I think a helmet and point fund went with it.
But each race had a expanded purse over normal weekly shows and they were scheduled against USAC most times

What made it neat though was that Tracks holding KISS races wouldn't run sprints against another KISS race.
This got increasingly harder to do with more tracks going to Saturday night only..