For anyone landing here, the following answer was provided (by a googler) on: Why use tensorflow gfile? (for file I/O)
The main roles of the tf.gfile module are:
To provide an API that is close to Python’s file objects, and
To provide an implementation based on TensorFlow’s C++ FileSystem API.
The C++ FileSystem API supports multiple file system implementations,
including local files, Google Cloud Storage (using ags://prefix),
and HDFS (using anhdfs://prefix). TensorFlow exports these as
tf.gfile, so that you can use these implementations for saving and
loading checkpoints, writing TensorBoard logs, and accessing training
data (among other uses). However, if all of your files are local, you
can use the regular Python file API without any problem.