Ed,  I too have heard the same expression since I started keeping bees.
My thought is; who are they (honey excluders) excluding the honey from?
Since I am a hobbiest and do not need to get all the honey so it really
doesn't matter to me.  If we follow bee biology they put most of their
stores above the cluster to be used through the winter. If we take it all
they will have to be fed to survive. When I use the excluder I know that
some of the honey will remain in the lower hive bodies which is a nice
place to have it going into the winter. :-)   Ron Harriger
                                              Cambridge Springs Pa.