Scarcity is a fundamental part of economic value. Diminishing returns is also irrefutable when examining economic systems, and the value of certain items in any given economic system. So why is it that most players, and the games they play, try to either ignore or control these two principles? While scarcity can be controlled to an extent, diminishing returns is more problematic, yet the two are rarely considered two parts of a whole.
While a great steak dinner has intrinsic nutritional value, most humans would grow to dislike steak if forced to eat only steak for years on end, regardless of its scarcity. Likewise, personal like or dislike for said steak dinners should not be based on how many of your neighbors are also eating steak, but personal like or dislike of a BMW would be affected by how many BMW’s are being driven by said neighbors.
We desire variation as an inhibitor to diminishing returns, and this desire for variation allows us to construct personal definitions based on our whims and desires. But our desire for variation is also determined in part by scarcity. This intimate balance of scarcity and desire for variation is what most games are not acknowledging.
Creating six similar variations of an ultimate weapon would not be difficult, and would be a much better than creating six copies of the same weapon, yet for some reason we always end up with the later. Variations need not be complex; equal DPS with variant min/max damage ranges, simple visible graphic changes, and/or skill based buffs as opposed to attribute based buffs are all easy solutions.
What game designers need to accept is that they are not arguing that this scarcity/variety relationship is healthy, or even that it should exist. They merely have to accept that it does, and then design their economies around it. Utopian ideas about consumerism, capitalism and greed need to be ignored when contemplating a game. Debate the merits of those factors in real life if you have to, but accept them as evil truths when designing a game economy.