Both Tolkien and Lewis wrote stories where a powerful lust for treasure is transferred from dragons to people via physical contact.
In The Hobbit, even after Smaug is dead, his treasure still has an aura about it that “rubs off” on the dwarves. They are already disposed to love beautiful gold things, but the dragon’s recent presence amplifies their desire to hoard it. Thorin in particular becomes very grumpy and protective – unwilling to make a deal with the neighboring elves or men.
In The Voyage of the Dawn Treader, Eustace discovers an old dragon’s treasure stash and takes a nap upon the pile. In his sleep he is actually transformed into a dragon, such was it cursed. It is hinted that the previous dragon was also a man who suffered such a fate.
It appears that in both their minds, greed has an unhealthy effect both on the hoarder and the observer. Sounds like imitative desire to me – which has been proven to often seem “magical”.