I think it's partly to do with what the noveau riche like to do - flaunt their wealth because they have no other ideas with what to do with it. As a result from getting a shitton of money from oil, everything from the palm islands to the dazzling skyscrapers was created in part to show off. This is why we have the puny man-made islands - clustered closer than a giraffe's spots - that you can buy and plant houses on to create some sort of eclectic rich people's beachfront commune. However, building with the intent to bedazzle first was also created to also attract tourists. Although selling oil is lucrative, it doesn't make sense to put all of one's eggs in a single basket, so to speak. So yes, fancy veneer to attract international money. People see the shiny buildings and completely forget that Dubai's central city planning basically boils down to what happens with people with too much money ignore the opinions of actual city planners and engineers.
A few miles outside of Dubai, though, it's absolute squalor because Dubai uses "contracted" workers, who often have their passports forcibly taken from them and are paid dirt wages - if they're even paid at all.
