It might seem that way to you.
But investing in development also means investing in infrastructure, and making livable cities. Cities bring in outside money, and hopefully, lasting economic change for the country.
Don’t kid yourself I’m thinking that the sheiks, royalty and oil barons of the area don’t know that petroleum’s days are numbered (socially and in regards to reserves). They’re investing into their own countries in the hopes of fostering lasting change. Yes, some may be despots, and the countries themselves may be anti-progressive. But many do care about the future of their home, regardless of their wealth or social status.
In the long run, it also benefits equality, as urban areas foster progressive ideology. See; Doha.