Flight instructors should at least tell their students
about what IFR fixes are and where they are (at that airport).
Its not rocket science and it will help the student in the long run.

That would require students to purchase IFR charts for every airport
they visit. They would not only need approach charts but enroutes as
well. Its much simplier to just tell the IFR pilots that they need to
use VFR friendly phrasing. Instead of saying "I'm at FOOBAR" they
could just say "I'm 5 miles out on the the ILS straight in runway 12".
Its not very hard.

-Robert, CFII

I can't see much sense in demanding that VFR pilots learn about IFR
and buy or download the approach plates so they can understand a radio
message from an IFR flight doing practice in VFR conditions (or when
conditions are VFR at the relevant airport).

Since there is no requirement to use the radio at class E fields,
though, then there's really nothing to be said if an IFR pilot just
doesn't want to be bothered.

This will probably never be such a big problem (ie, an accident or two
or three) that the FAA has to write a regulation on it. If they do
regulate, I'd bet money on the rule requiring IFR pilots to announce
position rather than the FAA requiring IFR knowledge from VFR pilots.
However annoying to the IFR pilot it might be.