I know this has been suggested before, but i really feel like this would be a great addition to the game. I love to collect mounts and transmogs, and seeing that i can't use an alt to farm a certain mount that's easier to get it with and have it on my main is a bit demotivating. A great example is rivendare's deathcharger, farming on a druid rather than a hunter ( my main) is 5x faster. Please have some thought on it! Thank you. :)
Exactly as you said: suggested, denied, end of story. Rules say so: http://forum.warmane.com/showthread.php?t=241277
If you want your character to look good you have to work for it, same goes for scrolls and transmog items.
If you're lazy, you've got the store to skip the grinding part.