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.
This is a good suggestion but it's a high cost form of advert if ever. And any regular bitcoin investor cannot afford the expenses, but only for those who have good amount of bitcoin in their portfolio. And I think it has already been done by some of the Bitcoin enthusiasts before but still the promotion until today is still far to reality.