In my opinion, you are right up to a point. Spirits are behind
everything from, a fantasy novel to an advertising to enjoying
life. Spirits entice you to try new things, either in the form of a
movie or the desire to upgrade your car. Can you safely say that
when we look at an advertising for the latest gadget or the newest
condo is NOT a temptation from the spirit world?
Strictly speaking, we live in a world engulfed by spirits. The only
escape is resurrection of the body. But when we are in this world,
can we shun everything (like the Amish community)? If we can't,
then the only way is to build a strong mental (as well as
spiritual) fortitude to allow us to live (an in many ways, mix
with) among non-Believers.
I guess the standard for shunning "witchcraft and wizardry" has to
be firm, if your stand for HP is such (which I respect), then you
stand for Chronicles of Narnia as well as LOTR should also be as
such. Going beyond this, the same stand should be held for Snow
White and Sleeping Beauty - the fact that these are Disney cartoon
should play no part in the stand.
Also we must avoid Journey to the West or Feng Shen Bang (Transl:
the ordaination of the gods). It is understood by the literary
world the such Chinese classics are written as political
satires.
Anyone having a strong stand on fantasy novels should also have a
strong stand on a Robert Ludlum novel or a Agatha Christie mystery,
afterall sorcery and witchcraft is not a greater sin than murder
and mayhem.