You do the god a little favor and he does you one. You bring him an offering and he owes you one.
This is not how God works. You ask and He responds according to His will. Not yours. There is nothing you can do for Him. He made everything and controls everything. Your worship is not a favor you grant to Him but only His due.
Even worse there is nothing you can do to save yourself, only He can save you through His mercy.
This is all terribly hard on the ego. And so you find another god, a little god, one that is not quite as holy. And you can make bargains with this one.
You hit the nail right on the head and it is a good summary of some of the points in the article.