Good point about the bugs, Indy. For example, I've seen many bundles of tightly stacked lumber turned into swiss cheese by carpenter ants while avoiding even the slightest bit of daylight.
But...
Protected space is usually at a premium for me so I stack without stickers. Just keep them it the ground and check once in a while.
That about sums it up for me too... protected space is a serious premium in my case, so dead stacked is my only option now that I'm literally thousands of bd ft into this. I have a 20x16ft 2 story shed packed solid, and another 3000 ft stacked in 9 ft high stacks in the garage. My Dad has a farm about 75 miles away and I plan to take much of it there for storage in the future for as long as he has the farm. I built an 8x16 platform there already, and plan on dead stacking on that with 2x4 frame covered with tarp. Important to let air through it though, and of course most important is to keep checking your stash. That doesn't mean just have a quick look, it means once in a while tear apart a pile or two and make sure its not full of bugs.
Bottom line is, unless you have a huge shed with lots of space in it, once you get up in the thousands of bd ft you really need to get creative. It's definitely an investment in time just keeping your stash bug and rot free. Nature of the beast... I consider it part of the whole milling/wood procurement experience. Slicing up logs is only the first step. Stacks of lumber are big, awkward and heavy and they do take lots of space. A 9 ft high stack of 12 inch wide 8ft long ROUGH lumber is around 700 bd ft of S4S ready to work. One thing I find difficult is storing large thick slabs because they are rarely symmetrical, come in all shapes and sizes and thus just don't stack well. Other odd shaped pieces like crotch slabs or unique carving stumps are another hard to store item.
The more I mill and get into this, the more I try and keep things as uniform as I can. Uniform board thicknesses, widths and lengths are so much easier to store and stack. My problem is I still have a hard time turning down non uniform stuff that still has potential. So... I keep it even though it turns out to be more of a storage headache.