For all those guys their identity is known. It would be easy to file a lawsuit and drag them in front of a court, but nobody seems to have the balls for it even though there's lots of big talk on the forum. Instead, everybody just accepts the losses and moves on, waiting for the next scam.
Well, it's "easy" in the same way that it's "easy" to climb Mt. Everest - the process is documented in any number of books and movies. So why doesn't everyone do it?
Even though we know how, actually going through the steps is expensive and difficult.
The problem with suing scammers is that by the time you actually win and try to collect, the money is probably gone - so the successful plaintiff will have spent money creating an effectively unenforceable judgment.
Judgments are interesting if you can get one against a person or an entity with a lot of non-liquid assets like real estate - they are not very interesting versus a person with no income, who provably knows how to get paid (if they did have income) in a difficult-to-detect/track fashion, and who has no assets.
My hunch is that none of the three people you mention have any assets to speak of - and certainly no assets that would remain following litigation, which gives them a motive/opportunity to spend their $ defending themselves, and/or transfer value from assets that are easy to collect against into assets that are tough to collect against.
This is why, in the real world, we often depend on things like bonds and insurance to protect ourselves against bad behavior - while lawsuits are possible, they're a very inefficient/unsatisfying way to solve problems, especially versus people with no assets and no income (known in the legal profession as "judgment-proof"). Also, most people aren't willing to act as quickly or as aggressively as they'd need to in order to protect themselves - e.g., seeking an order to freeze funds and appoint a receiver at the first sign of trouble, rather than waiting until the money's clearly been gone for several months, and then reluctantly filing a lawsuit with the cheapest attorney they can find as close to the expiration of the statute of limitations as they can get.