Ok, just reading your original post again. I think basically what you are saying is, "Why didn't you people order earlier?" Is that right?
I don't know if there is an answer to that. there are some pretty popular sites that do offer last minute air shipping at discounted prices. Maybe some people have only ordered from sites like those in the past and this might be the first time they ordered from a smaller businesses (assuming yoiu are smaller) and had to deal with the rest of the world.
Also, online Christmas sales are supposed to be up 15% this year, so maybe you are getting a lot of first time internet shoppers?. Maybe they just don't know any better.
As for me, next year I am going to have one of those "countdown clocks" on my site - seriously. This time I mean it. Really...
P.S., As for your workload, sure there are lots of things that would be very difficult for you to train others to do. So it is good if you can plan out your workload ahead of time, look at every "stupid" chore you are going to have to do (like buy tape or envelopes, or sweep or buy toilet paper, etc.,) and hire someone to do that.
I find that when I go shopping I can easily waste an hour at the supermarket figuring out whether I should buy the organic beef jerky or the regular variety, so maybe hiring someone to do shopping or chores for a few weeks will help you be more productive at work.
Anyway, have a Busy Holiday Season.