It is cruel if you keep it while other people dont have anywhere to live.

The bread was just an example. This can be anything. I mean communism doesnt mean that people can enter your house without your consent. If they need land to live, the society will give them one even if it means giving up some of your own land so no one will be left without somewhere to live but as i said, it will still become their property. So, there is nothing wrong about property ownership as long as you divide them equally.