There is a significant amount of government assistance that only kicks in when you run out of savings. So while not part of the tax code the disincentives are there.
Can you elaborate?
Resource limit for SNAP: http://www.dpw.state.pa.us/foradults/supplementalnutritionas... -- translation: "Have less savings, get SNAP".
Patient Assistance Programs at hospitals: http://abcnews.go.com/blogs/health/2013/03/28/real-money-hid... -- translation: the government says your hospital has to "give back to the community" by not making you pay your bill if you say you can't.