Doubt you're going to get very useful answers from the HN community tbh, even though a lot of posters here work for advertising companies.

I don't use an ad blocker and never have. It's fine, I'm used to it. Some sites are pretty horrible (mostly low end news sites). I subscribe to a handful of news sites which don't have any ads and that works out fine, most other sorts of sites have tolerable levels of advertising. If they don't I just go back and do without.

Why: the golden rule, pretty much. Not gonna be popular, but that's how I see it. Treat others how I'd want to be treated myself. If I browse someone's site whilst blocking ads, I'm consuming their financial resources but not allowing them to consume my attention in return, which is the "deal" implicitly entered into when I visited their site. Yes yes, it's not a written deal, you can make legalistic argument about it, but fundamentally the assumption website authors make is that people use browsers that follow the specs and will thus see ads, and ad blockers cause browsers to not follow the specs. If everyone did this those sites either wouldn't exist, or would have paywalls, and I appreciate the fact that they exist and don't have paywalls.

There are a couple of other related reasons.

I've been on the other side of this. I run a company and sell a product to developers (a tool for deploying desktop apps). We have tried ads, mostly text based. They don't work at all, presumably due to high rates of ad blocking. The number one feedback we get from missed sales is that they'd have loved to know about us earlier but it was just too hard to find us at the right time, and by the time they discovered us (often by accident) they were already buried under sunk costs. Targeted advertising is at heart about informing people about a product they might need at the time they need it. Because nobody is seeing ads, devs often end up wrestling with whatever MVP-level projects they found by following links from some project created by Big Tech whether it's any good or not, because they're simply unaware any alternatives exist. In turn this discourages people from just doing ordinary selling of commercial-quality tools, which leads to frustrating developer experiences.

I live in Switzerland where there are many rules that are very lightly enforced, for example, you can just walk on and off public transport with no ticket gates, and inspections are rare (my guess, 5-10 times a year even if you use it every day). My company's product is also done in this spirit: you can download it with no account creation or signups, the code isn't obfuscated, and it's free for open source projects. That policy is basically on the honor system with a bit of manual spot checking: if you declare your project is open source then the app just unlocks without payment unless we notice that you're lying. This sort of flexible trust-but-verify society is nice to live in but for it to work, it requires everyone to follow expectations even when you can get away with not doing so. I feel like ad blocking is similar to that. Likewise I could crack the commercial software I use and use it for free without being caught, but if everyone did that then the software wouldn't exist, so I don't, and I hope others will act the same way (whilst accepting that this isn't going to be true some of the time).

Finally, given the enormous extent to which the software industry is funded by advertising, it feels a bit hypocritical to block it. Consider how much of our collective developer platform is paid for using ad revenues either directly or indirectly (anything by Google or Facebook, even HN). If everyone blocked ads then at minimum Chrome and Android probably wouldn't exist, nor would HN which is justified partly by sponsored posts by YC startups. In fact it seems likely that there'd be no competitive open source browsers or consumer operating systems. I like that there are, and if that means advertising, so be it.