People weren't coming here for an easy life. They weren't coming here to get rich.
People came here in very large part because they wanted to worship God in accordance with their own beliefs, without having a King force them to do this or that. There were Quakers and Puritans and all sorts of people -- but they were overwhelmingly Christian. America was the land for Christians to worship God in freedom.
More than anything else, that is what America was founded upon.