You don't just have to 'silently watch'. You can warm others by voicing your concerns and stating why you think it is or might be a scam etc. You can also leave negative feedback as a warning.
I have previous experience in trying to bust a probable scam in Alt coin section, while a member with big
+ve trust appeared from nowhere and threatened in PM to leave
-ve trust because he 'thought' I was Spamming. I have seen before that people are wrongly attributed
-ve trust, but the people with
+ve do not cover them even after no evidence of SCAM is found. In this scenario, when
+ve trust accounts are on sell in a certain section, I feel it is better not to get into an unnecessary controversy as anyone can leave a
-ve feedback from a purchased
+ve trust account now.