Quote from: Davidbugs on November 06, 2018, 11:16:22 AM

Quote from: NeuroticFish on November 06, 2018, 06:44:19 AM

The pools, exchanges and probably other businesses do have full nodes, for their needs and for safety. Others can do this for the sake of decentralization.

Rewards? It can be good and it can be bad. Just look at the masternode coins; I don't like them, I don't find that model as safe and decentralized as Bitcoin.

Sorry if the question seems stupid. But I don't see what need an exchange has to run a full node...

To track in- and out-going transactions.

Because any third party an exchange relies on for receiving transaction data could potentially send them wrong data (eg. fake successful deposits where none took place or act as if a withdrawal has been non-successful even though it hit the blockchain) -- willfully or otherwise. The only way to avoid this risk is by running a full node by yourself.

Note that the very same problem is true for anyone using a SPV wallet such as Electrum instead of running their own full node. Difference being that you are likely 1) not as big a target as an exchange and 2) keeping track of in- and out-going transactions manually.