While it is part of the motivation, calling it the only purpose is just hilariously wrong, completely lacks any nuance/empathy, and a single case of something existing outside of the "only purpose" statement proves it wrong immediately.
My brother ex-communicated my dad because he wouldn't stop hounding him for money. My brother became wealthy at a young age, and made the unfortunate mistake of divulging his finances to my narcissistic father. My father made terrible financial decisions in his life and subsists entirely on social security. He also bragged routinely about cheating on my mom, who got the courage to pull us out of that situation when we were kids. Any extra money I have would go to my mom, not my piece of crap dad.
I can't imagine how terrible it would be if he simply knew how much money I make.