“A mob's always made up of people, no matter what. Mr. Cunningham was part of a mob last night, but he was still a man. Every mob in every little Southern town is always made up of people you know--doesn't say much for them, does it?”

Adams as portrayed in the HBO Miniseries John Adams (2008); this has sometimes been cited as having been actually said or written by the historical John Adams.
Misattributed

Pornography and Obscenity (1929)

Source: All the King's Men

Them Belly Full (But We Hungry), from the album Natty Dread (1974)
Song lyrics

"I Am the People, the Mob" (1916)

Kalden/Ty, to Mae; p. 488
The Circle (2013)

"Quotes", The Educated Imagination (1963), Talk 6: The Vocation of Eloquence

Vol. I, Ch. 1 : A Man of His Day, p. 17
New Grub Street : A Novel (1891)
Context: I maintain that we people of brains are justified in supplying the mob with the food it likes. We are not geniuses, and if we sit down in a spirit of long-eared gravity we shall produce only commonplace stuff. Let us use our wits to earn money, and make the best we can of our lives. If only I had the skill, I would produce novels out-trashing the trashiest that ever sold fifty thousand copies. But it needs skill, mind you; and to deny it is a gross error of the literary pedants. To please the vulgar you must, one way or another, incarnate the genius of vulgarity.

Source: 'Democracy on its Trial', Quarterly Review, 110, 1861, p. 281