The problem is that the "Deluxe/Limited" edition was not really "Limited" so people were kinda screw on that sense. Besides a nice faceplate there was practically no difference between reserving the game or buying it on day 1.
PD: combined that with one of Relic's post saying that there won't be any microtransaction/DLC which would affect gameplay (commanders)... But this topic is just beating a dead horse.
And to add to elchino's post, the deluxe version promised more before the THQ liquidation. Afterwards, the rewards were scaled back when SEGA took over. But I think most were generally forgiving, since many had warned of the dangers of pre-ordering, and their warnings certainly came to pass.
OTOH, I imagine, though I don't know, that most of those who made pre-orders were just grateful to something from the new game, as opposed to losing their pre-order payments and getting nothing at all.
Were the pre-order group happy with the initial retail iteration of COH2?...history tends to suggest otherwise.