System.out should not be used as a log record

In Avro-mapred:
https://github.com/apache/avro/blob/eab8e019d6452c5cf54c1278db51861ca9bf6aac/lang/java/mapred/src/main/java/org/apache/avro/mapred/tether/TetheredProcess.java#L219

Using system.out.print and log to print together, which makes me wonder, is this a specific intention?
If you change to log.info, do you have any other comments?