They might have been in their previous job a long time. They might have gained or lost weight since their last interview. Clothes don't last forever, particularly cheap ones, and the last suit they bought just might not be any good. To say that every person (or even most people) who unexpectedly find themselves having to seek work will automatically have suitable clothing in which to attend an interview is bonkers.

How are they receiving disability and JSA? How much of their income is from benefits and how much is from the drug dealing?
Discounting the disability side (that's either an abuse or not), they would only lose JSA by starting to work (over 16 hours per week. The rest of the benefits would stay regardless. So do you think an increase of around £4 per week (the JSA increase) would make someone earning £235 a week (full time job on minimum wage) say sod that I'd rather not bother with a job because now I can get £71 a week instead of £67?

You also still haven't answered how many people in the country have chosen not to work, and why a cut for millions of people in and out of work is justified.

You can claim DLA and JSA if the disability allows you to work: most DLA claimants claim ESA.
You state that they were assessed as single but lived together: normal for DLA as it pays for the extra help you need as care or mobility, not as a benefit for food etc.
However JSA/ESA would be affected by LTAHAW regulations and so could easily be assessed by the compliance teams in each JCP.
The earnings you state would nil any JSA/ESA on earnings rules.

Interesting you have not reported them but know they deal in drugs: such knowledge may mean your innocent status is besmirched by such knowledge: I am not a lawyer.

As a person on ESA, I have just gone through my paperwork which I receive every year. In the 9 years I have been claiming my IB/ESA (basic rate) has gone up by a grand total £15, increasing in small amounts ie £2 or so every year. My ESA amount has stayed the same for the last 3 years (2010/11/12), I got the 5% rise which was introduced in 2012 but because ESA is made up of differing components I received a 5% raise in one component only to have the next component reduced to exactly the same monetry amount so I received exactly the same amount whilst being shouted down by right wingers how disgraceful it was I had such a huge rise!!

My benefit hasn't changed amounts in 3 years and I will get 1% of £96 this April, in effect only changing by pennies in 4 years, and yet STILL benefit claimants are the scroungers, spongers and lazy workshy that can afford 50" plasmas, 4 holidays abroad, smoke, drink and buy drugs, eh Sal?

You do all know that it is perfectly allowable to claim DLA and work full time don't you?

And when PIP comes in and this government sneakily changed the criteria for claiming the high rate mobility component from not being able to walk 50 metres to 20 metres, a lot of disabled workers will lose their only means of transport (mobility car) of getting to work. Therefore that disabled, tax paying worker will have to go on benefits. Yeah very well thought through coalition, well done.

Not sure that it's as simple as distance someone can walk is it?

Sadly yes that is one strict criteria.

Yes its that simple as to whether I will lose my independence and become housebound or not. All the way through the consultations with disability groups and charities the government had set the criteria for getting high rate mobility the same as DLA, 50 metres. But what they didn't do with DLA was to ascertain as to whether you could walk 50 metres reliably, repeatedly, safely and in a timely fashion. If you could walk 50 metres in say, 10 hours, drugged up to the eyeballs on morphine, then you ticked the box "yes, I can walk 50 metres" and move on to the next question. No room to explain the pain, or why it took you 10 hours or the dosage of morphine, just a "yes I can" and get 0 points. (You need 12 points to get high rate mobility component). Then at the end of January they moved the goal posts even further (to the moon if you ask me) and dropped the 50 metres to 20 metres. They have no shame on what they are going to do to most disabled people, no shame at all.

Someone I know recently underwent surgery in which his abdomen was opened from the sternum to the pubis.
Four days later he walked 100 metres to the car to be taken home.
Was he fit for work?
Of course he wasn't.
But he'd have got the tick in the box for walking 20 (or 50) metres.

It's cruel and simplistic bollox to allow the rich to keep more of "their" money.