Thank you, friend.
PirateMike94
Is it normal that an instance that was once good, all of a sudden starts to lag, crash, not load, etc?
Yeah, potentially. Some bloggers live off of the ads their blogs serve visitors. So yeah, in that case it can suck. However, others make most, or all, of their money from affiliate links on their pages, or partnerships with other blogs, or a combination of 2-3 of these. I think you'll be hard-pressed to find a blogger nowadays who lives exclusively off of ad clicks/views, since that market has become increasingly less worth it even before ad blockers became more mainstream. One thing to keep in mind is that there are different types of ad campaigns, and if the blogger get paid per view or per click, in theory adnauseam could be triggering an impression and causing the blogger to be paid at the expense of Google/FB/etc. It really depends on how Google and Facebook deal with adnauseam's false clicks. So do with this information what you will.
Edit: Just as a matter of comparison. I knew a guy who, in 2008 built a blog where he had AdSense, and would routinely make £500 (~600 USD) PER WEEK, just from him clicking his own ads and changing his IP. Of course this isn't possible anymore nowadays (the change IP easily part) but also no way in hell Google would still be paying that much for as clicks. Those times are simply gone as Google, Facebook, Yahoo became greedier, not because of Adblockers, so you shouldn't feel bad for using them, imho.
Edited for added content.
I see, I was unfamiliar with adnauseam. In those cases then, in theory, you're harming all the interested parties.
You mostly hurt the owner of the website displaying the ad, if their platform depends on it.
Both the ad distributor (Google, Facebook,etc) and the business advertising are generally not affected because ads not shown aren't paid for. Advertisers pay per 1000 impressions (views, clicks, etc), so if an ad doesn't even load, it does not count as an impression and therefore the ad distributor doesn't charge for that impression.
More or less. Adnauseam could potentially be better for bloggers than UBo, but it really depends on how Google, Facebook, Bing interpret those "fake" clicks. If Facebook/Google can identify these clicks, they could make the choice of charging the advertiser regardless (and pay the blogger), OR exclude that impression (meaning the blogger doesn't get paid), OR, if they identify a particular blog attracts more adnauseam users than usual (perhaps a privacy/security-related blog), they could exclude the blog from their ad programs entirely. Please understand this is all highly speculative because we don't really know how these platforms treat fake clicks, if they are even aware of them at all, and so on.
I expanded further on how online advertising works on another thread in this post, if you'd be like to read it.