Yes there it is quite a lot correct in what you say @Lazykitten
I know quite a number of people who started work at 16 - back in the late 70s/early 80s in manual labour jobs like factories, foundries, building sites, and general blue-collar unskilled manual labour. They worked long days (8am til 5pm, Monday to Friday,) had 4 weeks holiday a year, and rarely had a day off sick.
Then came the age of around mid to late 40s, and they had to have some time off work after maybe 30-35 years of working (because of an accident or illness.) They had 3-5 months off on the sick, and realised they absolutely fucking loved being at home ... and not having to go to go out work. Some went part time afterwards, and then by 53-55 y.o. they went on the sick with a bad back, or depression, (or something else that kept them off for 4-6 months,) and they never went back to work.
Six or seven years later and around 60-62 y.o. and they're just holding out for their retirement now - and they have absolutely no intention whatsoever of going back to work. They feel like they've paid their dues and earned their stripes. 38-40 years at work (in an unskilled-labour grunt job,) and paying their taxes. And they love their leisure time - being with their friends, being with their family, being in the garden, going to the pub for lunch, going on daytrips, and being with their grandkids etc.
And like you say, at this age you know there's no way in hell they're going to get a decent job - except a 4 hour a week contract in B & M. So they just claim ESA and get their rent and council tax paid (some are homeowners and mortgage free,) and have a bloody jolly good life. Some people might say it's swinging the lead and taking the piss out of the system, but can anybody blame them really? To be quite honest, most full time, unskilled-labour jobs are absolute fucking pigshit. Who wants 52 years of doing that.... really?!