I just thought of this, and I want you to view it from your own perspective. As everyone hopes that more people get to believe and use bitcoins, I think bitcoins can gain more new users on a large scale if anyone (whales ) can place their advert through a popular football club just as some companies do sponsor football league. I think this will send a strong message to billions of people across the world who do know but does not embrace Bitcoin usage.
Let me site another example, let's take for instance, a club announces that they will pay their players in BTC. This news can also help people adopt BTC.
Sponsorships for football clubs are in the order of tens of millions per year, and usually there are big companies behind it. Bitcoin is not a company, there is no CEO, there is no shareholders, the only way would be that someone who actually owns thousand of bitcoins decides to simply sacrifice part of his fortune, but it's highly unlikely.