So because it was a gift, they have to stay 
ignorant to the value of the item?  That is 
ridiculous, IMO.  Most people like to learn 
information about what they own.  And value is 
probably the most important piece of information 
about a collectible item.  It's not like they 
want to know just how much Aunt May spent on 
their sweater for Christmas. :P  Its legitimate 
to want to know the value of a collectible 
piece.  Plain old curiosity, or the knowledge 
that if you are in a terrible money bind, you'll 
have something to help out, or if you want to 
trade with a fellow collector, or for insurance 
purposes, etc etc.

And after getting through saying they would 
never sell it, and what a big fan they are, I 
highly doubt that finding out it is worthless 
(which I'm sure it's not) would dimish it in 
their eyes, anyway.  So I fail to see what is 
so "appalling" about wanting to learn more about 
their item.