They have plenty of clean sand too...there's a world wide shortage of sand believe it or not! That oily sand stuff is polluted and cheap as Cheers H
Back in the late 1980's Saudi Arabia was, believe it or not, importing sand from Denmark. Apparently, the Danish sand was more angular (sharp) and more suitable for building purposes than the local offering.
On the right hand side you can play with the variables - perhaps in there? e.g. http://www.tradingeconomics.com/country-list/disposable-personal-income