They call this gambling, with other people's money. Another flawed thinking is their belief that paid between groups will make them become millionaires faster than if they are not in the paid group. There are others like this.
It's all about transferring responsibility to others with the thought that they are more capable of making better prediction than you. With that kind of mentality, it's easier for them to assume that joining a paid group will give them more win than relying on just on there personal bet. As a person, there's nothing wrong about getting some betting tips from others and occasionally joining some platforms to get some guides on how to make better bets, what's really the issue is being over reliant on them such that you don't trust your bet again. No one is too professional to know it all as regarding gambling, everyone is just making his prediction based on analysis that every other person can also do.