Most clubs will tailor their music, ambience, dress code, etc etc in order to attract a certain type of people.

If a club was created that played indie music and allowed people to wear jeans and t-shirts then I'd probably frequent it, but I doubt many others would. And those that did go would probably not spend huge amounts on alcohol.

So most hotels tailor their clubs to attract people who'll spend lots of money, which in Doha appears to result in Lebanese being the main clientele.

Alternatively they may aim to attract a huge number of people, who will spend a reasonable amount of money. The result being the same - they make a large profit.