Re: No permission is needed
No permission is needed - as things currently stand - to post content such as photos of other people - on to Facebook.
This depends a lot upon the jurisdiction but in most countries people do have rights to their own image and not just the weak as piss US DMCA safe harbour stuff.
However this case isn't about user generated shit, but paid for adverts where Facebook engages in a contract with the advertiser. The AGB's will almost certainly stipulate that the advertiser has obtained the necessary rights for the content and Facebook has a duty of care, after all it is being paid.
No wonder you got ridiculed.