Aggregator sites like coinmarketcap and livecoinwatch often show trends of greatest gainers/losers of the day/week/month/year. However, coins with almost dead marketcaps are prone to manipulation.
Why don't these sites remove such coins?
I think they have rules in removing those weak coins, this site only feeding data base on the movement of market trends. It's the investors responsibility if they will follow or not. Besides all crypto has a tendency to manipulate just to gain profits.