That is why I host my images on my own IPFS node. Unfortunately, I still have to rely on the central public IPFS gateway (ipfs.io) to make them available, as Steem is not integrated with IPFS yet (but it is in the roadmap). Ideally, media content would be linked by its IPFS path and retrieved using a site-specific gateway or a local node, so we would not need to rely on the single gateway server.