Glad someone agrees with me :) For what it's worth, I resisted adding .dockerignore as long as I could, basically for the same reason (why not add .gitignore support instead?) but the demand for it was simply too overwhelming to ignore, so I gave up and let it in.

See https://github.com/docker/docker/pull/3452 and follow -up mailing list thread.

In the end it kind of grows on you :)