rsyslog is putting log entries into an included file
Solution 1:
The include() object was only implemented from version 8.33, so the file= line is probably being interpreted as a filter selector of some sort, with an output to the file. You should stick with $IncludeConfig for your version.
Always check for syntax error messages by running rsyslogd -N 1, and if this shows no errors but you still have problems you can get very verbose debug with -d (add -n to run in the foreground).