I disagree. Exposing your users (including non-FB users who visit your website directly) to FB stalking isn’t a good enough justification (and in breach of the

I disagree. Exposing your users (including non-FB users who visit your website directly) to FB stalking isn’t a good enough justification (and in breach of the GDPR). You can track advertising effectiveness yourself by having all your ads point to a unique URL with some query parameter (“campaign_id=123”) which preserves the privacy of everyone. FB can stalk their users on their own properties but at least non-FB users are protected from it.