Indeed, This is a funny thing when someone will refer cmc for depend trading volume and considering projects liquidity. You able to focused only bibox exchange but you know there are many exchanges volumes are fake. Latoken,Vindex,p2pb2b,Exrates i would to told that its a 100% wash trading. Bibox is better from those terrible exchanges.
I don't think we can completely blame Coinmarketcap, because it only displays data from an exchange, I think if there is a fake volume or anything like that we have to find out for ourselves.
Of course we can blame that because coinmarketcap is indirectly help to promote wash trade exchanges. Why they including such of fake volume exchanges in their top rank charts? Coingecko is also providing these service but their analyzing is transparent. CMC is promoting fake ICO/IEO projects you can observe when we search coin price then you see a lot scammy projects advertisements.