Of course they come into the market to make money, and what is wrong about that ? That is just what about any trader makes. If you are not trading bitcoins yourself on this platform, you risk absolutely nothing. And this being said, I am not sure there is any actual risk, of any nature with those newcomers.
You're talking about the futures contract that the CME group is going to introduce, correct? First, that is a pure derivative. There will be no actual bitcoin trading through CME. But that doesn't mean that it won't have a huge impact on bitcoin. A bitcoin futures contract will allow large financial institutions to easily take a particular side (price will go up or it will go down). Once they do that, they could make up all kinds of news/FUD to manipulate bitcoin into going the direction they want it to go so they make money on their contracts. They might also find ways to buy into bitcoin directly in large amounts and hoard/dump coins at the right times to make their futures contracts more profitable.