Except they wouldn't be losing several thousand dollars by giving everyone who bought RotHC 1050CC's. They would only be losing the value of what those subscribers would have purchased but choose not to because of the "free" CC's.
if only they could do also do it in a way that's not making them lose several thousand (possibly millions) of dollars aswell,
nobody's suggested it but maybe giving everybody 1050 cartel coins and then giving people who bought it more then a month ago an extra 150 coins for every month they've already owned the expansion.
How many subscribers would have purchased 1,050CC's but instead would not because they're getting it for free? Some percentage, sure. And some will buy another 1,050 on top of the free ones. At $10 for that purchase it's not going to be a significant revenue loss.
It's like a store giving you a coupon. Yep, if someone comes in and buys JUST that thing, you miss out on some revenue. But those very few cases are more than made up for by others who come in and buy more stuff than just the couponed item.