Marx's famous quote that religion is the "opium of the people" is presented in"Animal Farm" as Sugarcandy Mountain. It's interesting that both of the words used to describe the Mountain, "sugar" and "candy" refer to sweetness, perhaps relating to sugarcoating a bad situation.
SugarCandy Mountain, in Christian terms heaven, is the reward that the animals will receive after their life of misery on the Farm. Critics of religion have often noted that those in charge of the state have often used religion to deflect concern from the citizens' present situation (since, after all, life is short) and turn their attention toward an eternal reward where they will be rewarded with eternal happiness while they can watch their tormentors on earth suffer the eternal punishment of hell. This has led to some horrible arrangements between Church/State as typified by the revolt against both the State and the Clergy in the French Revolution. In the words of Denis Diderot, "Man will never be free untill the last king is strangled with the entrails of the last priest."
The key benefit of Sugarcandy Mountain, therefore, seem to devolve upon the state which can use the promise of eternal reward to keep the Animals "accepting" of their rule in this life.
For Moses the raven, the obvious benefit was that he did not have to work. He could impress every one with his tall stories and eloquent speeches of the Sugarcandy Mountain and get paid for it,"with an allowance of a gill of beer a day."
For the other animals listening to Raven's seductive speeches about the Sugarcandy Mountain gave them some respite from the hard labour on the farm and instilled in them a false sense of hope of a beter tomorrow: "Many of the animals believed him."
As far as the pigs were concerned, Moses the raven was an enigma but they continued to tolerate his presence on the farm even though they dismissed all his accounts of the Sugarcandy Mountain as lies.