Doesn't this seem a bit "low stakes" to want more disclosures about? I view it in the same light as say someone who posts makeup reviews or video game reviews on YouTube- often it isn't their primary source of income, and the item value (<$100) seems notional. Maybe it can be treated as more of a deal if a company were to attach stipulations or keywords for the reviewer to mention, at which point it should be treated as a partnership rather than a less-than-impartial review. I subscribe to independent creators on Patreon because bias is nearly impossible to avoid when there's a quid pro quo of getting a stream of free things from companies.