In pursuit of happiness

I've read an article about materialism and our culture's tendency to choose 'to have' over 'to be'.
Why do we decide to focus on material things and put our happiness and self-evaluationidentity in them?
The author of the article suggests that we very often want to show off to other people because we lack self-esteem or we try to compensate for the lack of time we spend with our family by buying them expensive things. We also lay put other peoples' opinions before ours.

There are a few things we can do to change that, and we should explore what we really need to be happy, instead of just gathering newer, greater, popular stuff. Give careful thought to our audience; think if about whether we really do need it, or get something because whether we want it or because we are trying to catch up with others or be in the centre of their attention. Who are the people from whom we seek acceptance and admiration? Are we putting our motivation outside of ourselves? Are we trying to be like someone else? 

On my journey through life I've discovered that it is wise to search for motivation inside us and not to follow the crowd. It's not about being a rebel or that original freak, it's about being honest with ourselves.