When the poor start to starve...
Why wouldn't "the poor" decide to produce something instead of starving? Why do you think so little of "the poor"?
Why do you think they are not trying 'to produce something' at the moment? Being poor is for most people not a choice, but something they are working very hard to escape from.
If you actually looked at a crowd of "the poor" in the US, you'd conclude they're not in danger of starving any time soon.
Hunger is a serious problem far before people start to die of it. It makes people less healthy (and hence productive), it makes children do less well in school, and it also encourages criminal behaviour to get some food on the table. There were very good reasons to introduce food stamps in the US (even apart from the subsidy to farmers, I mean), and they are exactly the kind of investment that even the most psychopathic should approve of for entirely selfish reasons.
Keeping the masses reasonably well off...
In a free country, there wouldn't be "the masses", nor would anyone be "kept". Free people are individuals. They make their own choices.
Where is that utopia you are dreaming of? It is certainly not the US. Possibly some of the scandinavian countries that have a reasonable balance between socialist and capitalist ideas.