Not arguing either Dave.
A lot of these "nurseries" that supply (read flood) the market, unethically this time of year, do it more so to make a quick buck and prevent expensive over wintering of the trees, in their greenhouses. Reputable organization normally overwinter them in sheltered hoop houses (read no heat), and will seldom if ever sell out of season. It is extremely expensive (part of doing business) to maintain greenhouse settings during winter (dependent of course on location). Trees that find themselves in big box stores will surely succumb the ordeal as the majority of the staff do not have a pea picking clue how to look after them. The individual Vance is referring to is the exception not the norm, and very few will over winter a Juniper successfully indoors, I know I lost one.
It was a "Procumbens" and against my better judgment, was convinced by the owner of the bonsai nursery that it would be fine for one season, the tree was acquired 3rd week of November, purchased on a business trip. When I say against my better judgment, I offered the owner to pay now deliver later and pay all expenses until coming spring, it was a no go (need to make room). The tree was healthy, was in proper bonsai substrate, followed the nursery owners recommendation to the letter, and just watched it go downhill and expire. All attempts to salvage the tree were in vain.
So when I say one should never buy out of season, it is sound advice. Anyone who manages to keep one alive inside overwinter, has gotten lucky, nothing else (with the exception of Jack Wickle).