Why is the market for NCLTC so small?

I personally like "Coin of the Realm" and "Non-Circulating Legal
Tender Coinage" because of its commemorative value, aesthetic beauty,
craftsman****p, and often elegant presentation.  Why then is this not
enough to create a larger market for these coins?  These coins come in
all shapes, sizes, metals, and finishes.  Many have exquisite
application of color.  Some are even sponsored by iconic names like
Charlie Chaplin, John Wayne,  Marilyn Monroe.