See https://bugs.jython.org/issue2896. Short version:

1. Jython before 2.7.2 used its own logging mechanism to the console via Py.writeError() etc., called within the run-time, which did not make a record in standards-based application logs.
2. In 2.7.2 Jython began using the java.util.logging (JUL) to report these events in logs.
3. In the case of the console application only (jython command), we take control of the logging process and format, to produce succinct messages on the console alone, for an assumed interactive user.

A user records a preference that we not intervene from the command-line jython, or at least make it trivial to turn off.

This was a conscious design choice, but maybe it needs adjusting. Revisit before beta.