Social standing plays a large part in happiness - just because people on the other side of the world may be worse off it doesn't change the fact that being worse off (in terms of quality of life) compared to the people around you is very detrimental to an individual's mental health.Hay just think you're a white male in the UK with a job and roof over your head.
How more lucky do you want to be.
People who live in misery due to having no food are not suddenly made happy by the fact they have running water, neither are victims of abuse thankful of having a room - or any other western novelty.