Aussage des Entwicklers:

Q: Will i store other people's stuff?
A: No, by default IPFS will not download anything your node doesn't explicitly ask for. This is a strict design constraint. In order to build group archiving, and faster distribution, protocols are layered on top that may download content for the network, but these are optional and built on top of basic IPFS. Examples include bitswap agents, ipfs-cluster, and Filecoin.