No one can swear that he/she never put a mask in his life, whatever may be the situation.
We don’t show our emotions to everyone especially with whom we are not familiar. We want to show our good side only to them. Sometimes, even to our good friends or close relatives, siblings and parent we hide ourselves behind a mask. We have lots of masks. One for each role and each situation. I think it’s okay and it’s only natural but we will be damned if we wear mask in front of a mirror to hide our emotions from our self?