I agree with Anthony up to a point here. Bad decisions can be useful, you can learn from them, and then turn them into a useful lesson, especially in the business world. Broadly speaking people doing stupid things should accept the consequences of their actions.
However where I diverge is that, I personally don't like to assume everyone is "making a decision" in the sense that they are making a concious free-will driven decision to perform act A or B (and apologies Anthony if you weren't suggesting that is always the case).
I think some of the reasons people do things, is still yet to be explained by psychologists, psychiatrists and Neuro-science.
We know some people have split-personality issues, phobias, addictions and generally accept the plead of insanity in some court cases. Therefore I think we could argue that decision making processes can be irrational and are driven by factors that the person in question may have no control over.
Does childhood trauma affect the outcome of the adult? Is it rational for society to arbitrarily choose a date from which henceforth the individual is held accountable for all their actions e.g. at aged 18?
I'm not sure we can just answer these questions with a simple model of "decision making".
This of course shouldn't be justification for a nanny state, but maybe we should recognize the need for safety nets in some areas and if the government isn't to provide it, should at least help to facilitate it.
