In all fairness, this doesn’t sound like an exactly fair comparison. If it’s a small business with only 6 people (7 including the owner) then he’s a lot more exposed financially than a larger company. It means he doesn’t have any of the protections that a larger or incorporated company would benefit from. If anything major goes sideways, then he’s finished. The workers can, in theory, pick up and go find a new job somewhere, but the owner could be financially ruined (this happened to my dad and he never recovered. Although to be fair to him, he busted his back working alongside everyone else, sometimes even longer than them).
The amount someone gets paid isn’t always a direct ratio for how much physical effort they put into something.
I don’t know your boss or anything, so I’m not trying to contradict you, I’m just pointing out something that came to my mind.