Apparently, people are getting banned because they accept gold from those who bought it. Even if they don’t know the gold was bought.
Be careful out there. If someone tries to trade you a large sum of gold it’s probably one of your enemies trying to get you banned 
Source: “Dude, trust me.”
Here you go. Looks like it’s if the gold is mailed to you.
https://www.reddit.com/r/wow/comments/1aq1dmk/ls_starcraftlol_asked_blizzard_cs_on_twitter_if/
its true asmongoloid and some people on classic season of discovery got banned for accepting gold from the mail
oh no, it may sound like that but asmongold a youtuber of wow share a video about that, it is real
To be honest, this kind of just sounds like someone bought gold and got caught, and then they pretended they didn’t know why someone was trading them the gold but decided to accept it anyway.
I don’t have friends so any time I get stuff in the mail that’s not from the AH or the Postmaster I always return it thinking it was sent by mistake. I don’t wanna steal someone’s gold they were trying to mail to an alt! 
That Blizzard ticket image is too blurry to read.
My take away also
Sounds a lot like a forum post earlier today that got moved to CS forums:
And they were NOT banned for trading gold, not at all.
Is it just me or does that Reddit post sound like, “I bought gold, it was sent to me in the mail and now I got banned, but I’m going to spin it like I’m the victim”?
i volunteer as the guinea pig. Will be accepting gold donations in order to confirm and fact check OPs claim
Look, my DARE classes made it clear that if people give me free stuff I’m supposed to accept it without question.
Such a noble sacrifice. What a hero 
No, it’s legit.
Buried in the chain:
For reference: this was the post the original guy, LS, used as evidence of the exact same issue where it was overturned.
I wish Blizzard would just communicate instead of having us theorize that’s all we can do this is a real issue. We’re told not to accept gold from people we don’t really know or can face such actions, it’s impossible to vet people every single time if their gold is legit or not.
What if my best friend I play with all the time buys gold and gives me it without saying? Idk if they even glance at the context.
As for SOD, it’s pretty obvious if gold is bought IMO, if someone drops a fat stack and you’re locked to level 35 id be wary of it, not saying its impossible but I feel like 3 thousand would be pretty rare for an average player. But makes me not want to interact with trading at all unless done in AH.
All I’m saying is idk, and I hope if this is a true issue they will come out and tell us whats up, but doubtful. Just don’t bother trading with people period.
In this case, it’s not about accepting said gold, it’s literally just getting it in the mail lol.
Word for word your reply applies to me as well.
lol people are actually getting banned for this. go check the classic forums.