Well, to be fair, the only real reason to donate at this time is to get the donation creatures, and people don't like putting money down in advance for something when they don't know how long it will take to clear up the current problem (in this case, the people that got massively egg-locked by the Snow Dragons and who now want the very temporarily available duckits).
Expanding the time window would a most likely make people more comfortable with donating to get an egg, because they're not feeling the need to scramble for their event creatures.
We have a month to get and hatch a doni creature. We have 1-4 days to get and hatch as many event eggs as we can.
EDIT:
When I say 'real reason to donate at this time' I mean the benefits. Yes, donating right now means MS stays up and online, but outside of that...

















I ninja click siggy eggs. *kung fu pose* 


















) then I can help save the best egg place evarrr. 

Thanks guys!
















It wouldn't default to 4 duckits and 2 donis. Limited durations eggs> other eggs, always, that's just how the vast majority of people work. So since no specific mention of doni eggs being separate, that's why I brought it up again. That, and I have to admit that I haven't read all the thread.
It just seemed like the most logical answer, and also one of the easiest to implement.