Punky, I think that "kingdom interests" in Watchtower talk ultimately means feeding the personal pride that each member the gb has in perpetuating their imagined privilege as a "God's appointed."
"Kingdom interests" and "serving Jehovah" are among the rally cries of the gb... all result in greater wealth and glory for the governors and more personal sacrifice in the live's of their flock.
But hey! It's not working at the moment... to keep that glory they need the money and hence kingdom interests demand they resort to humiliating begging and stealing.