I believe this strategy is not new, this is just part of the marketing strategy, maybe some will say it's a bad strategy but some may understand. However, the most important is knowing the site is legit and has the license to operate as that means regulators can investigate and they need to comply with certain rules and regulations.
Anyway, thanks for bringing this reality OP, some may not know it's happening.
Marketing strategy to attract more gamblers to try it out and see how luck permits them, but it's always gamblers responsibilities with all the actions. I get OP's intention and it quite good to bring this attention to those new to this kind of advertisement. There's always the other side of the box in each streaming/vlogging business, they will receive payments, they just needed to make sure that they'll be bringing traffic and possible gamblers to use the site services.
This is happening even in a land based casino, so it's not surprising that its happening in online casinos. It's a classic strategy for most gambling business as that's the best way to attract gamblers to play in their establishment (online or land based). It could be cheating but as long as no one complains with evidence, that would not make them guilty of facing any legal charges or whatsoever.
I guess it's important that every gambler has to be aware of this marketing strategy as its a basic thing to know.
Like what I've said from the post I quoted above, it's the gamblers responsibilities to know all those basic thing that happened around.
Never to take any action just because of those influencers, it's your money and you should take the full responsibilities behind.