The problem with someone saying "They have to earn my respect" is that you have to watch them to the 'respectful' things. However, if you in the military and you see an officer, you don't question whether they have earned your respect, you give them respect because even if you didn't see them graduate their officer training, they have done it and have achieved a position worthy of respect. So yes, they earn the respect, but even if you have only known them for 5 seconds, they still receive the respect they would have earned had you watched them complete years of training.