"They've got to be stopped," the Oscar-winning creator of "Fahrenheit 9/11" told reporters ahead of the press screening of the new work in the lineup for the coveted Golden Lion here.
"There's one home foreclosure, one family kicked out their home, every seven and a half seconds. That's a stunning number," he said.
"Wall Street is trying to figure out a way now to keep getting away with the crazy gambling game" that sparked the financial crisis, he said, noting that gambling is illegal in most US states.
He said he hoped the film would spur ordinary people to action.
"People have allowed Wall Street to decimate the industrial infrastructure of our country to achieve greater profits. All of us are part of this machine that has to change," he said. "Wall Street, corporations, government and the American people (have) bought into the system."
Pressed by a reporter to explain why he accepted funding for the movie from Paramount Vantage, the specialty film division of Paramount Pictures, Moore agreed: "Why would these corporations give money to a guy who is diametrically opposed to everything they stand for?"
His answer: "The capitalist will sell you the rope to hang himself with if he can make a buck on it."
Noting that all his films, from the corporation-busting "Roger and Me" on down, have made a profit, Moore said: "I get a sense that they don't really care what I think or believe."
He said he wants to "get to this day when I won't be beholden to them and can make films with my own money".
The film will premiere at the world's oldest film festival on Sunday.
Also Saturday, the 66th Mostra was to present "Persecution", the story of a rudderless youth and his well-anchored girlfriend, the first of three French films competing for the coveted Golden Lion.
From Hong Kong's Soi Cheang is "Accident," a tense thriller about a hitman who "choreographs" murders by making them appear to be accidents.
And quirky German director Werner Herzog was to unspool his matricide drama "My Son, My Son, What Have Ye Done?", the first of two "surprise" selections for the main competition.
The selection was doubly surprising because Herzog has already shown his zany cop flick "Bad Lieutenant: Port of Call New Orleans" out of competition here, where it is rare to have two works by the same director.
In "Persecution", Daniel, played by Romain Duris, renovates Paris apartments where he sleeps when he is not with Sonia (Charlotte Gainsbourg), who has a solid job that often takes her out of town.
"The renovation jobs are a metaphor... of Daniel's search for a centre, for a reason for living," director Patrice Chereau told a news conference.
While fighting inner demons, Daniel becomes the obsession of a male stalker who claims to be in love with him -- and paradoxically becomes one of the only constants in his life.
This element of the film earned it selection as a candidate for this year's Queer Golden Lion, a prize independent of the Venice festival that has been awarded the past three years to movies with gay themes or content.
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