Think of the varying reasons why people use incognito mode.

The advertisers have chosen to show the advert to this group of people. I can forsee incognito mode users being targeted more and more for any adverts relating to personal security, cyber bullying and as - in this case personal attacks.

While people think incognito mode makes you anonymous it actually puts you in a sub group of people who are admitting they are highly aware of personal and online safety. The adverts shown will become more aimed at this.

Keep in mind what Google does. They don't give away your personal details to advertisers. Rather they offer demographic profiles of an anonymous group to advertisers. In addition the advertiser does not know who sees their ad other then that Google thinks the viewers are within their target demographic profile.

Apparently that organization bought ads for a profile you fit. It does not mean Google thinks you are a victim of assault.

More likely the advertiser is on a Google Grant and their SEM manager has created bids on a plethora of keywords since the money is free (and limited at $1/click).

incognito: with the identity disguised or hidden

Google doesn't know who you are, so results are not as relevant.

But still the ad is not even remotely related to jquery image hover effects.

Don't advertisers pay Google to deliver ads to people who are looking for relevant info ?

They tell Google which keywords the want their ads to show up for and related keywords. While it may seem completely irrelevant, someone might be bidding on random keywords that triggered the ad.

Oh. I guess Google does not monitor if people are bidding for keywords relevant to their business.