So I think you might benefit from a bit of commercial business dealings that offer context: The NFL has an exclusive contract with Nike. A player, Robert Griffin III, signed an independent endorsement with Adidas. That means to do his job, RGIII could only wear Nike branded shoes on the field. He protested by taping over the Nike logo when he was out on the practice field, as a point of principle.
The league - his employer - reminded him of the conditions of his employment. There was nothing preventing him from wearing Adidas from HEAD TO TOE as long as it wasn't in a direct situation sponsored by his employer. Thus, he actually had TWO sponsorships in some terms.
He wanted to wear his Adidas on the field, but was not allowed, even though it was completely above the board. So, where do you draw the line? Can your employer tell you what brand of clothing to wear? If he got the shoes for free, should RGIII be allowed to undermine the other contract?
My perspective is that the line of reasoning you present is inherently flawed. Are you not aware that Nike essentially got its foothold (pun intended) by giving away shoes to college basketball programs and people who probably couldn't afford to buy them? It was covered in an ESPN 30 for 30 so there's the citation.
From your context it sounds like you believe - maybe it's my interpretation - that things given to celebrities for free are "no strings attached" and I think that's been proven wrong time and again. Contracts, handshake deals, they don't work that way. There's either an explicit (preferred) or implied (bad) debt to be paid. It takes time to learn how these systems work, and woe to those who might minimize their practical implementations.
Oh, and a Youtuber who receives free stuff better disclose it, because if they're in the US, then they have the IRS to deal with. The IRS doesn't screw around with compensation. Dollars or donuts, keep the receipts[1]!
[1] Excluding Mitch Hedberg, who accurately pointed out a donut in regular guy life does not need a receipt.