The page says "ads". There's nothing wrong with writing software that makes money. There's nothing wrong with putting ads in the software. There's nothing wrong with not putting in ads. It's a defensible decision either way, I was just curious and thought I'd ask, and maybe learn something.

Kind of wrong to use another site's content and make money off of that.

Tell that to Google...,

They make almost all of their money from other sites contents and providing a service to make finding the content easier.

You and me both. I see enough ads as it is and there are HN clients just don't show ads, so not sure why I would change to use one that does. It'd have to be a really good client.