I have been different means that people were scammed before using sport as their means. Some people will not listen or not know until they are scammed already. If they can umake 80 to 90% of money with betting, no need for them to be telling people to invest.
It is when it is turning to a means of encouraging people to invest or to come for a paid subscription is when you have the red flag that it is a scam.

You do not need to wait until they scam people before you should let people know that it is a scam. As long as money is involved, it is a scam that is available.