Imagine you you had a magic button that suddenly increased demand for a volatile security any time you pressed it. That would be a fairly valuable thing for some people.

If I have information that the price of x coin is going to go up and my friend knows I know, then they just need to follow my trades and they can make money too.

If enough people follow my trades then this can generate demand and actually affect the price.

It’s in their interest if other people copy their trades because the asset values will go up