What i also hate from CMC is they don't delete any token/coin which has been delisted from exchange and just keep showing their stats even though there is no any market. That's make the number of token/coin they have keep increasing
Coinmarketcap is an aggregator of coins and their statistics.
If they would start removing coins because they got delisted then there would no way for investors who bought those coins to keep track of them. A dead coin may get revived which is the dream of main failed investors.
Also removing coins is a radical steps which will bring in a lot of backlash on the site from the communities and this will lead to its downfall. After all sites like CMC and others depend on user views, donations and traffic to keep the site running. There are already some sites attempting to predate on its downfalls. Get my point?