Well, you seem to have understood that the first part was a joke. Still you slip back into your didactic arrogance in assuming that others don't know as much as you think you do. The fact is, depending on how one defines anything, you'll find it whereever you want. Perfect example, chain gangs are somehow considered a form of slavery by you, but "light" forced labor is merely acceptable. Trying to have your cake and eat it too? The type of work isn't what constitutes "slavery", but rather the situation one finds oneself in (forced labor, with no real ability to opt out). One more onerous to be sure, but both forms of forced servitude.
Unemployment is one type of assistance. Welfare, at least over here, is different. Either way, it's government assistance with no real return to society. Many have stated that expecting people to have to perform any kind of service in exchange for this support to be tantamount to slavery.
Once again, though, as I didn't actually challenge your contention about "legitimate" slavery, you actually refuted nothing and reduced nothing to irrelevancy. However, as the only form of actively state sanctioned "slavery" you contend is prison related, it does relate to my intial point about how you define slavery explains where you will see it.