i was not aware that the current respawn time was the retail respawn time.
Warmane however i a different environment, on retail there are currently 3 places to get the pipe, on warmane there's only one, furthermore, realm will not be progressed to further expansions than they are at atm, Wotlk servers will always be wotlk, mop will alwyas be mop, and cata will always be cata, so to keep absolutely everything as retail was is just not long term effective.
I recall in old molten the spawn rate was like 15 minutes, and the hog was still pretty expensive as it is now (was around 25k), except the whole profiteering and boring camping wasn't there.
And if warmane really wanted to keep the hog as rare as Mercy claims it to be intended to, then why did warmane put Shadowmorne on the donor shop??, that's not preserving its rarity whatsoever.