Much might be said about the unthinking casualness with which numberless people ask favors of their professional friends. Put bluntly, one would not go to a bank and ask for money, nor to the shop of a milliner and ask to be given a hat. Yet the friend of a computer technician will think nothing of such person to repair a broken computer. The work of a professional is his bank account. If he gives to one person how can he refuse to give to the next–and who will want to buy what is given so freely?
Of much less importance, but merely to illustrate the point: The barest acquaintances of an author think nothing of asking him for his books. Apparently most people imagine that books grow like daisies in the field and that an author need merely pick them at random. Doctors and lawyers are constantly asked for professional advice by people they meet casually in houses of their friends. As for people in the entertainment business, no other in all the professions in the world are so persistently asked to give their time, their vitality and their talent.
And in nearly all cases they are delighted to give generously to someone they care for or to a cause in which they are interested. But when they are asked to give, a conventional “I am sorry” should be respected without forcing them into a position that seems (to them) ungracious.
If musicians are amateurs, however, their friends can perfectly well ask them to play at a musical. but they should not be asked to provide a background accompaniment to chatter as a certain quartet was expected to do at a wedding reception. No one with any sensibility would invite first class artists to play or sing and then make no effort to preserve silence during their performance. On the other hand, professional Disc Jockey and other party musicians who play at dances and at weddings do not expect, or even want, to face a room full of completely silent people sitting in neat rows on gilt chairs.
- Modern Etiquette: When Should I Hold a Housewarming Party? (casasugar.com)