This is just moo, but unless something in the garbage bag was found with true evidentiary value, I don't think it's a big deal.
Concerning the bag itself, many people lift it out of a container with the drawstring and never touch the sides. LE friends have told me that items can be covered with prints that are smudged and unreadable. I've rolled over 2000 fingerprints myself for FBI checks and even when one is trying hard, small imperfections can get them bounced. Pressure, the amount of oil on the fingers, all kinds of things can interfere with getting a useable print for recognition purposes. With a partial, or with only part of a legible print you still need a certain number of identification points, or minutiae to make a clear recognition match. That's hard enough to do when you're trying and you have the entire finger or palm; it's much harder when people handle things and don't use their full finger or swipe something.
It does look on TV like recognizable fingerprints are everywhere, but that is not always the case. It is often very difficult to get fingerprints clean enough for positive identification of an individual or that would hold up in court as such. Zero prints does not necessarily mean no fingerprints whatsoever, as in wiped clean; it can just mean no identifiable prints. From the way I read the report no prints simply means no recognizable prints in this case.
But let's look at whose fingerprints should be on the bag of domestic trash - KC and anyone living at AL's apt. So what? The only reason fingerprints would be of interest, is if Caylee's were on something in the bag, to show she was alive while KC was staying there, and children's fingerprints fade more quickly than adults. So even if everyone at AL's including KC had fingerprints on items in the bag, they would only be of interest if a specific item in the bag had evidentiary value. Empty food cartons just don't relate to the crime as far as I can see. A knife, a bottle of medicine or something else would be of value and would make fp identification important, but old receipts and Velveeta cartons are pretty irrelevant to the case or to any alternate scenario we've seen or imagined.
I sense absence of a "stranger's" prints seems to be bothersome for some reason. IIRC, the date of the trash bag and its contents post-dates the expected time Caylee's remains would have left the car, so a bag of trash being put in (perhaps to simply cover the smell already there) the trunk by KC herself does not seem to have much evidentiary value. If it were somehow retrieved by someone else, it would require a cumbersome and convoluted story as to how they got access to KC's car and trunk to begin with.
