I may be going a bit O/T here, but there are a few misconceptions in this thread.
(From a NSW perspective), generally, a prisoner having been found guilty was sentenced by the court to Hard Labour (in the case of incarceration). It's not Hard Labour as such, but was a term used during the sentencing process way back.
The weekly pay into the prisoner's gaol account is about $15.00pw, but more if certain work is undertaken, especially if requiring skills (e.g., Kitchen, Bakery, Laundry, furniture, metal-work, cable work, and many more) where available. Some work provides for bonus incentives where production targets are met/exceeded. The type of work available often depends on the type/location of the prison (e.g., at a Prison Farm, work may be more rural orientated - summer/winter vegetable production, lucerne/hay, afforestation, cattle/other livestock) whereas elsewhere it may be more industrialised, or centred around hygiene/cleaning work, but can vary a great deal.
Refusal to work, in the case of sentenced prisoners, may have repercussions such as restricted access to amenities while others are at work. It may also mean, in the case of Minimum Security Prisons (which are generally "working gaols", where prisoners have actually agreed to work), transfer to another ("less desirable") prison.
Prisoners with long sentences want to work, and for as much of the day as possible. They understand that it will help to pass the time. In some cases, they may be able to obtain some skills for the future.
Prisoners in modern times have received a wage, whether they bought tobacco or not. Going back some years, this wage was the equivalent of a pouch of (White Ox) tobacco and some (Tally-Ho) cigarette papers, although the comparative costs blew-out long before smoking was banned in gaols.
Regarding refurbishment of Qantas headsets, this is very low-skilled work. Pretty much basic "cleaning", reassembling, repackaging, very routine/repetitive and undertaken in some cases by prisoners with intellectual disabilities ("sheltered workshop" type work, without trying to be demeaning, here).