Possible that Stake paid Drake in order to post the slip on Twitter, but knowing Drake's gambling habits, it's not entirely unbelievable for him to place such a huge bet amount using bitcoin. Then again, what's suspicious about this is that most of his bets were on Stake, not only on the sports category but also on other games hosted by the platform. It's sneaky and also deceptive if ever, but legally there's nothing wrong if he didn't disclose it as an ad (I stand corrected on the legal part.)
They certainly have the money to do it, if they were able to get so many famous people to represent them, but if anything like that came out both Stake and Drake would lose some credibility. More probably they gave him some discount to play and posting the screenshot was his choice. It was an expensive ad by Stake because he won a lot of money, but I'm sure it will be profitable for them in the long run.
If we're talking legal stuff, do you really have to disclose every single deal you get. Say you get a free tesla from Musk. Does driving it and posting pictures on social media count as paid advertising? If there was no contract between the parties that made you post these pictures, there's no obligation for you to even disclose that the car was a freebie.
Now they are gradually turning into fiat and are completely under the control of banks and regulators. I do not like it. Better a tough war than strangulation in "friendly" hugs. By the way, as I understand it, Drake made bets using not cryptocurrency but Canadian dollars.
