|after ice storm|
Tom Scott looks at the question as to why social media influencers (and that presumably includes bloggers like me) must disclose conspicuously if they were paid for commercial promotion of a product or service or received a free sample to review (like a free DVD of Vimeo link of an upcoming film, which I often do). In a sense this makes a post an "advert". These are FTC requirements in the US. YouTube has additional rules so as not to confuse advertisers.
On the other hand, commercial broadcast television does not have to make these disclosures (nor do normally produced motion pictures) because normally the audience is presumed to know the context already. The UK is a little stricter about this than the US, however.
The basic concepts are “payment” and “control”.