"Lord, what fools these mortals be!" (Act 3, Scene)
In Poul Anderson's A Midsummer Tempest (London, 1975), Oberon comments on Puck:
" 'Forgive him, Prince. Unaging Faerie folk too oft blow rootless on the winds of time, and ripen not to wisdom like you mortals.' " (p. 48)
In Neil Gaiman's The Sandman, Shakespeare writes A Midsummer Night's Dream and The Tempest for Morpheus, in return for inspiration, and Shakespeare's company first performs A Midsummer Night's Dream before the court of Oberon and Titania shortly before the Fair Folk withdraw from Earth. They might have less reason to withdraw from the alternative Earth described by Anderson? - but I have yet to reread to the end of the novel.
(A Midsummer Tempest 1-V are on the Poul Anderson Appreciation blog.)