Rocky...& others,
If you were, let's say set up and selling RMKs at the Blade show, you could sell an ivory knife there...as long as that buyer did not "live"...or "transport through" one of the ban states.
OK: WE, meaning the forum owners or moderators have no way to control who sells what and where in our "buy, sell, trade" forum. "If" someone violated these laws, even innocently, "WE" could be held accountable as "WE" were the vehicle for the transaction of this illegal activity and sale.
Hope this helps,
Capt. Chris