I'll chime in with my own personal view, to add to a variety of opinions here.
I play since the EU open beta and a founder / lifetimer.
Do I feel entitled to something special and extraordinary, like a heap of mithril coins, as someone suggested here? Not in the least.
Do I think that every year the gifts should be more lavish and extravagant? Certainly not!
Am I disappointed with the 10th year's gift? A bit.
Ten years is a huge milestone, and I'd like the memento of this year be memorable, most and above all. The fireworks don't fall into this category for me, sorry. I'd rather prefer a unique cloak.
Would I throw a tantrum over it? Of course not.
Of course I would be glad to have the Dragon fireworks but it's not really an item one would use all the time. Just my 2 cents.
Spiders in V1 Pre-B13: 8-legged menace. B13: 8-legged bait. B14: 8-legged trap... no more! B15/MoM: 8-legged *splat!*
Spiders in V2 B7: We cope. B8: FotM? B9: 8-legged menace.
Spiders in V3 B3: Mourning for my hatchlings.