<< OK, opening up the burning program takes ....5 seconds, burning the CD would take about 1-2 minutes then, making the image...what ??? >>
making image....nero....cdrwin....clone cd.... u have to make images with those programs (i could be wrong).  and i hate easy cd creator, so i won't go there.  lets not forget that with a zip...u pop it in and drag & drop.  ease of use is also a factor.  when "putting" stuff on a cd...its not as simple.  and like u said....burning a cd would take 1-2 minutes.  i think saving to a zip would not take that long.  i'm not saying the zip is almighty, but its still a pretty useful medium.  
btw, for those who say its too expensive...no one is asking u got get like 50 zip discs.  all u really need are a few.  i use my zips for transferring data...like from my work pc to my home pc.  after i get it copied, i take it off the zip.  if i really wanted to have a backup, after i transferred the files from zip to my home pc, i would burn a cd.