Sit-ins became a tool in the 1960s for those whose power was much less than those in power. In fact, it was the only thing they could do to effect change - draw attention to the actions of the powerful - just look at them and you will agree that what they are doing is outrageous.
This sit-in by House Democrats is only one of many symptoms of a system that is slowly breaking down. Much of the mainstream press is skeptical that this action will accomplish anything. These are the pundits who understand that establishing democracy in countries that have only experienced authoritarian regimes, but fail to understand that restoring a functioning democracy in the U.S. is a long and difficult process.