Perhaps we are not satisfied with how others are treating us. In any event, there are those times when we like to escape the reality of our current situation and imagine that things are different. This is not necessarily a bad thing to do. Sometimes it can be the first step in making things different. It's not bad to dream, especially when they are good and when we make a commitment to translate those dreams into reality.
Sometime dreams can be a positive thing.
On the other hand, sometimes we pretend, not in order to consider what could be but in order to ignore the reality of our own situation. This can be a bad thing, especially when we need to deal with our situation by facing it squarely. There are times when God desires to bring us face to face with who we really are in order to change us in to who He wants us to be. This is precisely what the Sermon on the Mount does. Jesus' great sermon pierces the veil of pretense and reveals a true perspective on life.