Yes, this may seem like overkill to you and I, but when you have so much wealth what would you do??? Yes, you could donate to others but we have no reason to assume he hasn't already done so. Some people invest in businesses and stocks....this is a business!!!
I'd imgaine with 60 stories and a staff of 600 there are indeed going to be live in staff as well. So he's created 600 jobs and probably also housing dozens of people besides his family. Wow, what a great way to invest in real estate, live comfortably, and still fuel the local economy.
I could see 60 stories filling up rather quickly if you had a staff that large and unlimited financial resources.