But other people have the checkbox set to permit unobtrusive ads.
I don't, and everyone I set up doesn't either, and it isn't because I hate all Ads. It's because I hate Removing Adware and viruses.
All of the unobtrusive ad's I've seen from adblock plus contain some link to a malicious download. Don't believe me? do the VLC Test.
1) Turn on Unobtrusive ads
2) Go to Google (or Bing, or Yahoo, Or Ask, ETC.)
3) Search for "VLC Media Player" (As a side note, DuckDuckGo is the few Search engines that do this right, but still serves malicious ads once in awile. Use "Libreoffice" or "Openoffice" Instead of VLC for an example)
4) Click on the first link you see. If the first link you see is an ad, click on it.
5) Download the installer ***WARNING!! Do not run it unless you Enjoy Cleaning viruses for fun!***
6) Go to virustotal.com, and submit the file for analysis
7) Watch the detections go off the charts.
I get roughly 3-7 pc's a week in our shop infected by adware caused by malicious ads that would be otherwise considered unobtrusive. If ad firms would clean up their act, and refuse malicious content ads or obvious scams then I would be more receptive of turning it on. Until then They're no different than a trojan downloader to me.