I don't have any experience using them but I'll remind you that coinmarketcap has been known for making their records modify and pumping the volumes of the exchange they want to even it's not real.
I don't the coinmarketcap are the one to be blame for exchange fake volume listing because the last time i checked the volume showed on each exchange site is what capital market bot updated but if we are talking about coins fake listing then there's a chance that capital market may be part of the volume modifying.
I see some videos on YouTube where they tell people to register and they will get some tokens, but the main problem is they ask KYC, and i really can't trust all new exchange sending id and all on just for some of their tokens which may worth dust, so is really people choice.
You're right but only the newbies will fall for such a trick because the token they are going to give will worth nothing. Aside from that, their KYC issue is pain in the butt.