One of the harshest ways the poorest can end up paying is by being out of work.
True. But then you get to the whole issue of the responsibilities of the welfare state.
If - to do a deliberate
reductio ad absurdum - the whole country were out of work, then there would be zero productivity, zero output, zero GDP, and entirely unfunded consumption. That would of course lead to a death spiral of debt. In the real world, Greece is in a minor version of that spiral, where the huge numbers of unemployed and consequently low GDP - coupled with a level of consumption that has not fallen by a proportionate amount - means that Greece is in a horrific situation (one from which I think it's wholly unlikely to recover unless there's a Grexit and massive devaluation of the new Drachma).
Clearly, an advanced society has a responsibility to provide a decent safety net for those who are either poor, out of work, unable to work or too old to work. But the solution is not to keep increasing benefits - especially in times of fiscal hardship. The solution is to try to stimulate growth, so that more jobs will become available, so that more people will be lifted out of poverty, and so that therefore the "safety net pot" has fewer people to service (and thus the fewer people who need the safety net can get a better safety net).
In the same way, the best solution to reducing public borrowing is not to place an even higher burden on the wealthy than is already imposed by the state. It may
sound like a great solution - especially to class warriors and naive politicians - but in practice it usually has the unintended opposite effect. Just ask Francois Hollande about it
Like it or not, in the current environment, the only sensible way to reduce public borrowing is not through increased tax rates, but through imposing tight controls on public spending - and the main areas of public spending are the welfare state, health and education. Education and health are (rightly) ringfenced on account of their universal benefit and their long-term importance, so it's inevitable that most of the cuts will come in the area of the welfare state.
(For clarity - as per Rat's indignation - I'm not suggesting you don't know this subject well. I'm just trying to expand upon what you wrote)