I forget where but somebody had proposed a system where society's currency was replaced with karma points. If you had a high amount of karma, people would be obliged to care for you and make sure you are sustained in society. The ones with low or negative karma may end up killed in a back alley and so forth.
I really thought about the circumstances of such a situation and I realized we already live in such a society today. The people who are capable of bringing the most value to society are often sought after for universities through scholarships and such, in addition to almost being guaranteed a job. Those who don't have very valuable skills and are hence aren't able to bring much value to other people are left searching and building themselves for opportunity or to be cared by the altruistic few that happen to gain value from them.
Is my conclusion correct?
It sounds like to me the aforementioned Down and out in the Magic Kingdom. However, I disagree with your use of the word "obliged". Also, even if someone has a low or negative karma, killing them should still be objected too.
Also check out "And Then There Were None
" (simple readers guide
which is a non-automated system of life without money.