When are you present? Now? You might think so but if you consider your day most of the time your mind is somewhere else thinking and feeling its own thoughts and reacting to them like it would to dream images. Being present is crucial for spiritual growth. Otherwise your reactions come from habitual selfish thoughts and emotional reactions. They take rarely into account the whole situation and also the situation of others and how you could by your own being bring more peace and joy for others in different situations.
This is why presence is practiced in dream yoga day practices. You start to notice what is actually happening around you and not just thinking wishful thoughts you mind wandering elsewhere than here. When your mind and focus is primarily somewhere else you can not experience stable and balanced peace and joy of being. Being present and realising where you actually are is the exact same process that happens in a lucid dream. You notice the wonderful and colourful outer world and realise this is a dream. You become present and awake to the reality of your situation.
In the first day practice presence is trained many times a day by becoming present in your outer senses, and practising at the same time recognising a dream at night. If you never think about dreams during a day you have no reason to do it at night when you are dreaming.