Italy Rejects Reforms, Matteo Renzi Announces Resignation
wsj.com
wsj.com
http://www.economist.com/blogs/economist-explains/2016/09/ec...
People felt that Renzi didn't have the right to be the president. People thought that Renzi was a liar, that the constitutional reform was only a way for himself to get more power. So many people voted accordingly to their feelings, not basing their vote on what they tought about the reform. Italy's vote is the result of an irrational hate directed to the establishment. People thought they were "saving" the Constitution. Not joking. In Italy people don't know how many articles are there, when the constitution was written and in which situation it was written. And then they pretend to "save" it.
Sorry for my english. Oh, and that's the opinion from a "yes" voter.
It would have been in their interest to campaign for Yes, but their mission is to capture the anger of the average voter so they found themselves having to campaign for No to push Renzi out instead.
The movement was entirely born on the web, and refused to appear on traditional media like television and newspapers, as they believe traditional media to be undemocratic and corrupted. The focus of the movement is participatory democracy, so they coded an online platform where citizens can propose laws, discuss, and vote on them. These proposals are then brought to the parliament by the elected members of the movement. These are not career politicians, they are common citizens elected on the online platform based on their CV's. It's probably one of the first big experiments in direct democracy.
So, to answer your question, they "believe in" what the majority of citizens believe in. The only constant is they believe in the democratic power of the web.
I think it can be called anti-establishment as it was born from strong negative feelings against the current establishment, and it refuses alliances with any existing political party. It gathers people across the political spectrum, who are unhappy with the status-quo. It's a very interesting experiment, testament to the disruptive power of the web, as the managed to get ~30% with no presence on traditional media and no campaign financing.
Think Donald Trump meets the Pirate party.
The Spectator has a good article about them http://www.spectator.co.uk/2016/06/beppe-grillos-m5s-is-a-sc...
Don't make the mistake of thinking the referendum was a victory by them though; there were a LOT of people against Renzi, including half of his own party (who openly campaigned against him)