>Where I live out in the country there are a lot of people with those kind of businesses. They bring you the goods and services to/from in a truck. If you ask to look at what they have... they have no address and won't tell you anything more than their goods/services dropped from the sky.

Yeah there's a fair amount of that here too.

Thinking about it on a meta level I think on the "low end" it's basically just a hack around how expensive employees are when you consider exposure. Sure you could have your $15/hr guys stay late and power wash your box trucks, deep clean your facility, etc, but some guy with a van will come in and do it on the weekend for a flat fee and if he falls off the ladder that's not your problem.

And on the high end it's a hack around overhead. You can have some guy show up on a jobsite, set up a tent to keep predatory eyes off and weld up the broken thing on your backhoe or the rental company calls that guy and repairs it on your job site without telling you giving you deniability. No expensive compliance costs of adding hot work to your job site or running a shop where that stuff happens regularly.

>if I am happy I would rather not know.

Always better to be able to say you don't know rather than "I asked and the answer seemed fishy but I didn't probe".