Like with all things it's probably wrong to assume only a single facotr is true. More likely it was a combination of several factors that made broader changes possible.
Players wanting easier character changes. Shifting views on in-game purchases. If not descent, at least a revenue plateau in WotLK. Potential new leadership or influential shareholders.
Could be lots of reasons for Blizzard to add stuff like the in-game shop.

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can't queue for bg blitz because too low ilvl problem...
Warcraft as title too "intimidating"
MMO-Champion








But the whole point of this patch for void elf fans are the high elf combos. I think he is kind of out of touch? No offense 




