I understand your point.
Unfortunately, you can't blame the GM's over a decision that was made by the players.
It's the players that have inflated the runic kits lobbying the next CUB. It's the players that decided it was a logical choice to hoard as much as possible in preparing for a CUB event.
CUB is not something that has to be done in exactly one way, it's something that's done at some point in order to relieve the server from stress, and to reward long lasting players. The result will still be the same, and I'm that if, and when, there would be another CUB, it will be fairly rewarding to all of the player base, instead of selectively rewarding to the players who have been hoarding for a year hoping for something that is not necessarily meant to be done on a regular basis.
Let's take a fun comparaison.
Let's say it's been a year you have not cleaned your house, and then you decide it's time and you clean it, scrub it up and down floor to ceiling. At your wonderful surprise, you manage to find 20.00$ in coins and bills that you lost during that time.
Now since that happen, would you think it would be a good idea, to intentionally dirty up your house until it's such a mess, in order to clean it again and hope to find even more than the 20.00$ you found before?
Of course not, it's a bit silly of an example, but to me it's kind of the same principle.