I have often wondered myself. I find this very annoying since I try to avoid "Noids." Also, I save the name tags of all my orchids that die so I can replace them. All too often, the big box stores have large and showy orchid plants (usually phals and dendrobiums) which upon closer inspection have rotten roots and possible pest problems. They also sometimes have a stressed appearance, which any orchid would get after being shipped and put in an area without proper light and too much water. Still, I can't argue with the point of view that this introduces people to orchids who might not otherwise buy one.
The economic downturn has affected me adversely and I have had to cut back on buying orchids () I am trying to avoid the big box stores because I will see cheap orchids and end up buying them. I have to go and buy a sprinkler soon and I must exercise willpower.