Direct democracy enables citizens to vote for every service imaginable and vote to pay no taxes for them.
http://www.telegraph.co.uk/news/worldnews/europe/switzerland...
But the US government seems to be doing a pretty good job of just that.
http://en.wikipedia.org/wiki/File:CBO_-_Revenues_and_Outlays...
Representation rather than direct democracy does not help at all here.