Why would he try it, though? He's an adventurer, and a merchant on the side. A slave owner, with slaves specifically skilled in dungeon adventuring and fabricating stuff using materials from monster drops. His common sense is different from the locals, but he's actually living a good life by following the customs of the locals. A pretty funny situation, but also quite commonplace. Even in our world when a person moves to the other side of the world, to a different culture, they will typically fare better if they try to copy the local customs and follow the local way of living to a certain degree in the new society, regardless of their own common sense. The difference is just more exaggerated in isekai fantasy.