It does quickly grow to be a silly number of clicks, and a whole lot of Marble. Thing is, we don't know much yet about what we're required to do.
This is unclear:
and after the mix up in the Anniversary event window text causing so much strife it needs to be clarified. Does only the first Golem on each Island count toward the Server Golems or do all Golems count?
Even if all personal Golems do count there is nothing yet that says we must each kill five to make the goal, clearing as many lower level ones as possible may be enough and looking at the rewards currently on offer; 10 Pumpkins for Golem1, 20 for G2, 30 for G3, 40 for G4 and 50 each for Golems 5 and above with a server-wide reward of 100 Pumpkins each if we reach the unkown goal, it's probably wise to consider 'cost vs reward' at some point.
It may also be that the tally rises with "Quests completed" and so Golems killed too early do not count which would have badly skewed the server totals that were showing on the Test. That we can kill Golems too early and break the quest chain really does need to be sorted sharpish.
Until these things are clear we're more or less guessing blind.
If the event runs as last year it's also worth remembering I think, just how long three weeks is, in Settlers Time it's simply ages. We're not in a race with other servers this time either, Golem hearts are made as quickly as Balloons were (Sorry, I know, I know. But it is the same time; 1 minute 40 sec for 1 in a Level 1 Provisions House, 1 min 40 sec for 2 in L2, etc) and we can help friends with their Golems directly so it seems it may not be that big a deal if Prov does something else for a day, the Golems aren't going anywhere.
Of course without more information much of this is just guessing too and as the whole thing is still "testing" there is time for change. All that said, and while it seems to me wise to look a bit beyond the worst case scenario, I do completely agree that if we all must kill at least 5 as they are now, by ourselves, for the rewards as they stand then the whole thing is indeed entirely too much another massive click-fest/resource sink. But again, right now we have no real idea what is required and that may not be the case at all. Some clear and accurate information from The Powers That Be really would be very much appreciated and might possibly go a long way toward improving many people's opinions of the coming event.
Edit: The test server homepage is worth a read just now: http://www.tsotesting.com/en/homepage
Hallowe'en has been removed for the moment but it looks like it's coming back tomorrow along with a load test (Date: Wednesday, 18th of September Time: approx. 12:00 - 18:00 CEST,) if enough people log in and play there are rewards for the live game on offer. Just as a heads up.