Power is what they get addicted to after they amass so much wealth that money nearly losses all meaning and becomes just a way to compete against the other richest people in their social circles. They most definitely do all this for money, because money is how you get to the point that you can then be a power broker and start hoarding and abusing power to amass more power. All money is power to a degree, but not all power is money. They hoard money as a foundation to build upon as they amass more and more diversified power outlets with which to play god and feed their narcissism.