Used to work as an expat briefly in some of these factories, all grim by our standards but by local standards often not. Queues round the block to get work people walking 40 miles for a chance of a job.
Any how, I remember an engineer spilling a load of oil, the supervisors grabbed handful of 501’s to wipe it up rather than use paper towels etc.
There will be a difference in quality with the Tesco ones but it’s in the design and while the Tesco ones cost a couple of quid to make a pare the 80 quid Levi’s cost 3 quid.