I don't care who you are, where you work, what job you hold, what you drive, what shoes you wear, or who does your housekeeping. It is not ok to treat people like they are your slaves as if there were not another person on earth that could possibly be more important than you are.
Ask, do not demand.
Be grateful, not dismissive.
Try smiling instead of scowling.
Acknowledge someone else's existence for once in your priveleged life. You might be surprised at the results.