Sounds illogical to me too, which is why I do 
much prefer getting artbooks, posters, prints, 
pencil boards, playing cards, etc.  The only time 
a cel is particularly appealing is when the 
character it has on it doesn't have much other 
merchandise, like Kouga in Inu Yasha.

^_^ I'll never see the value of 'limited edition' 
or 'one of a kind' or 'signed by so-and-so' so 
you're arguing with the wrong person.  "It's 
pretty" is the only reasoning that works on me 
when it comes to that sort of stuff.