I don't like Qatar Airways...Everything about them sucks...service, food, airfare cost...flight always delayed. 

So you only get good service if you fly business class and forget about it if you travel economy?  That's not fair.  Their advertisement is misleading.  They should specify in their advertisement that 5-star sservice is only for business and first class.

I believe economy class passengers also deserve some good customer service.  Economy class make up the majority of the airline revenue.