For example, imagine getting rewards for making correct match predictions. Cool, right? And no, it's not betting—you're not putting in any money. It's actually a cool feature; as a Real Madrid fan, I could leverage this to gain some liquidity if I'm lucky.
This is cool if it is free and real. But speaking of reality, there is no way to gain and win right predictions without having to bet with real money.
So, it isn't cool at all unless there is some conditions from the exchange that you are advertising and that is an incentive for specific accounts and users that has spent certain threshold.
Besides, I've never seen an exchange that sponsors a football club doing a prediction contest, it doesn't exist I guess, exchanges are more focused on other things not guessing match scores.
Except for casinos sponsored by new clubs, there are many prediction contests, and this is not easy, it is not completely free, there must be a wagering requirement to get a withdrawal from this contest.