Servants are not democrats. In general, they approve of the social order, just like their masters. And they intend to take advantage of it. A stable groom might aspire to become butler or steward in the same or a greater house. The pot boy might hope one day to be chief cook.
Servants take money from anyone.
They expect to be vailed for delivering a gift or message. Their masters are aware of this, and do it themselves to other people's servants. It is not considered dishonest unless loyalties become confused and compromised. The good servant, like a good waiter, is attentive. The best servant is a little bit psychic.