This is true.
Further, you have no idea where the gold you get came from. That would be considered an “unsupported” transaction and if it goes wrong Blizzard would not help you. You could end up the recipient of illicit gold and suspended or banned as well. Then you have to fight a whole appeals process to try to get that fixed.
Just rock your legacy name and keep it. Not worth the possible hassle, in my opinion.
Yes and no. If the char is over level 30+ it holds the name for 30 days for the Battlenet Account. Letting someone use it for another of their own chars.
That was a bit old so I will edit if it has changed.