You respect them because you where told to respect them by someone you respect... So why do you respect your parents?
There's a difference between respecting someone and being obedient to that person.
Boss is obeyed by all, when he is nearby, everyone courteously greet him and kiss his *** . Then during the job, while the boss is away(this is common specially in the case of obedience through intimidation):
__He is a jerk! I wish I could get another job as I can't stand him!
__Yes Bill, he is a

, I wish I could say it straight at his face!
__Don't worry pal, one day we will have the chance of teaching that ******* a lesson!
__Quiet! He is coming!
That explains pretty well the difference between real respect and imposed "respect". (Well it's tough to describe this without using expletives, but all are covered up, so those who know them will guess, those who don't, won't know)