People want to be happy and all other things that they want are typically means to that end. Even when people forgo happiness in the moment they are usually using so in order to increase it's future yield.

Once we have an experience we cannot simply set it aside and see the world as we would have seen it had the experience never happend.

Not knowing what we're missing can mean that we're truly happy under the circumstances that would not allow us to be happy once we have experienced the missing thing. It does not mean that these who don't know what they're missing are less happy than those who have it.