To be honest, I think this is just like piracy. "I block them because I can and is easy for the average Joe".
People saying "yeah, I block them but let the good sites to show me the ads" is probably from the same ones saying "I download music from torrents but if I like them, then I buy them".
People saying "I don't trust any script from ads because they will hack my computer" is probably the same ones saying "I don't buy music from the RIAA because they are evil" or "If they didn't have DRM"
If you think ads from Ars are bad, don't visit them or send them an e-mail.
And don't come with the "They should change the business model", well maybe they need to but it is not that easy and come on, if they charge $2 dollars/month for a subscriptions everyone will whine and say "no no no, I can get all the content free on the Internet or other website", then, if that is the answer, GO to the other sites already.
*sigh* burning karma