The market caps on a lot of altcoins are hugely manipulated. Consider one of the original manipulated altcoins: Ripple. They premined all the coins! That is, they created all Ripples beforehand and only released them to the public a bit at a time.
There’s a huge amount of Ripples that are being held in reserve so that the actual float (that is, amount available to the public to trade) remains relatively small. Many premined coins do the exact same thing to manipulate not just price but their market caps. Only a small portion of the coins actually are traded while a big reserve sits on the side owned by their creators to keep the market cap of the coins high. Even the news are being manipulated, banks are not using XRP for bank transfers, they are using the technology underlying it, so don't get hyped into this bullshit and thinking banks are going to buy more XRP as they aren't, only idiots who believe that this is happening are buying into it.
This isn’t anything new and in the stock market, stocks that play float manipulation games generally become juicy targets for short-sellers. Altcoins like Gnosis, for example only floated 5% of their coins, so ask yourself, how much of Gnosis’s $115M market cap as of this writing is real?
If that isn’t confusing enough, also consider that many of these Altcoins are actually subcoins of Ethereum and much of the market cap may be double-counted. This bullshit needs to stop, the crypto world is being driven by these manipulators which is against Satoshi's original intent of a decentralized currency, it is becoming very centralized thanks to: Greed, yes alot of people starting buying these other coins because of the opportunity of making a quick and easy money. Lets take back control of our cryptos and stop buying into this bullshit.