This is a good argument for shipping an empty config file.

Your point stands, but this also isn't completely unintuitive. There is pattern there: you installed samba and the config is in /etc/samba/. System level installs will almost always install their config in /etc/ and the sub directory will typically match the name somewhat.

There is likely a general thought that if you're going to administer a samba server, you'll also be comfortable with conventions and man pages. Although, funnily enough, in the particular case of samba, man smb.conf doesn't show the path lol