This is very popular everywhere, especially here in our country, mostly are in social media, where some of their video include advertising any gambling platforms, and these gambling platforms pay a huge amount of money to these personalities, especially if they have a lot of followers.
These celebrities do not only advertise but also share their referral code to their followers, in fact, celebrities are the only users that earns much from their referral unlike a regular player. The sponsorship gives them the chance to showcase their ref code to everyone repeatedly before, at the middle and at the end of their videos.