"The most basic reason for that is a classic free-market narrative. If you believe in freedom of choice, and companies having the licence of society to operate, that is justification enough to work there. This may not seem especially purposeful: many employees would regard operating legally and serving customer needs as a requirement rather than a source of pride. But it is a perfectly coherent position"

It's less about bad/good and more about whether the work is fulfilling I think. Gaming is a lootbox gambling hellhole now, yet people love working on games, so they keep flocking to it, despite the objectively negative impact of microtransactions, systems designed to maximize addictiveness [1], etc.

[1] https://www.destructoid.com/ea-filed-a-patent-in-2016-to-tin...

I've been approached a couple of times about working in the tobacco industry and money is definitely part of it, but there's also a feeling that there's less competition so the role will be more stable, and a lot of self justification from hiring managers to make you feel less guilty.