I worked in day labor for less than two days. Day labor is, needless to say, low-skill and high-turnover. But there are still dangerous jobs to be done. My job involved directing a wet-vac to pick up water, inside a store, while the other guy was grinding or something that needed to be wet down.

I am a nerd and my glasses were falling off from the sweat. I think I was wearing a pair of work boots which may be required. But the guy giving me orders on-site was not my employer. These clients are well-aware that day laborers may not be back tomorrow. So why give us durable safety equipment that costs money? The day labor office is my employer, but they may not be accurately informed about the safety requirements of the client and the site. They may require us to purchase safety equipment at own expense, but if we don't know what the site requires, or how long we will be there, that's an up-front expense we are unwilling to part with.

Day laborers are one step up from the guys hanging out in Home Depot parking lots, whereby they are legal to work in these United States, but can't get a job anywhere else.

So it's a 3-way tug-of-war of vagueness and parsimony, and it always just ends up being nod-nod, wink-wink, do the best you can.

Car mechanics have a few cultural things that lead to everyone buying a preposterously expensive box of their own stuff. First is theft (stuff walks away a lot) and second is flat-rate differentiation. Having the right tools can make a flat-rated job take much less time and thus incentivizes the mechanic to have their own tools, and still would even if the garage provided them.

Not saying it's good or right, but there are incentives that push towards it.