I can't think of many examples in which magic is used as the primary method of acquiring, well, everything the kingdom needs, but it is interesting to consider how materialism acts as a dividing force in fantasy. Individuals who hoard and who must own things are seen primarily as the enemy, or are at least on the darker side of the good guys.
Harry Potter, perhaps, is one of the few series that so obviously presents oppositional forces in the world of materialism--a good and evil battle between the kinds of materialism we are familiar with today. The Malfoy family dominates much of the series as the principle nemesis family to Potter and the Weasley's: they are wealthy, pride themselves in said wealth, and spend it with the express purpose of acquiring new and flashy things; they are the pinnacle of materialist families in the Potter universe. Harry, however, is exceptionally anti-materialist. Most of his possessions are those he has acquired not necessarily by intent, but through gift or necessity--and each of those possessions is "special" to him, having something to do with his family or his friends. Potter isn't interested in acquiring things so much as hanging on to his links to those most important to him; the Malfoy family, however, is the opposite. And, of course, Potter is the hero, the good guy, the Chosen One.
These things are seen elsewhere too. Karen Miller's The Innocent Mage/The Awakened Mage series splits society into two distinct groups: those who typically support the King, and those that believe the King's family doesn't deserve to be where they are. While each of these groups are in a position of privilege and power, there is a particularly strong materialist bent in those families that do not typically support the King. These "darker" families want the throne for purely selfish reasons, while the "lighter" families want the throne to protect the Kingdom. Even the King's magic-less son is opposed to materialist formations, rejecting much of what has been forced upon him as the son of the King. There are even splits within the royal family as well, with the princess being particularly arrogant and selfish, despite her parents' level-headed approach to authority.
But what about materialism in fantasy that isn't definitively evil or good? How does magic influence the way the material is perceived? I can't think of any examples, but it seems to me that if a select few individuals in a society were to have magic and were also not inclined towards ruling "normies," wouldn't there be a rejection of materialism in general? Why would you be a materialist if you could create anything you needed out of thin air? What of Gods? Why is it that in fantasies which contain Gods as active participants, that they are often materialist in nature?
Perhaps there's a bit of faulty thinking by fantasy writers in certain instances. It seems illogical to have materialist tendencies in societies in which magic alters the consciousness of select individuals, or even where entire societies are magically inclined.
But maybe this is what fantasy does: it steals from modern society and drags it into the fantasy landscape, even if the analogy doesn't quite compute.
What do you all think about materialism in fantasy? Let me know in the comments!