Ads?
What are these things that you call "ads"?
Google Search ads paid for by US and EU government agencies and legislators, and by major companies, have been spotted in embarrassing and legally dubious places, including sexually explicit websites, plus sites in Iran and Russia in possible contravention of economic sanctions. Adalytics, an advertising metrics firm, on …
Beyond advertisers' desire to keep their images "unsullied" by not having their ads appear on websites not approved by them -- which is a reasonable desire on their part -- what harm is being done? If a person in an embargoed country views an ad for a drone, or a 340-hour Dolly Parton DVD set, that doesn't make them any more-likely to be able to break the embargo and obtain the goods/services in question. As for FBI jobs, I'll go out on a limb and suggest that "U.S. citizenship required" is on the filtering criteria.
>Clickety-click< ... At the FBI job site (I had to click on [APPLY NOW]), I see that "Special Agent" is "POSTING TYPE: All U.S. Citizens". The other POSTING TYPE seems to be, "Current Permanent Employees".