Yes there are import bans which by inference ban sales, but the primary barrier is the law against import, not sale.You're right I stand corrected.
But there seem to be plenty of items that are illegal to import and presumably sell (and I stand to be corrected again) such as asbestos, food related items containing lead, unlicensed radio transmitters, certain plants, animals and drugs and many more
I tried using Google to find a list but this is the closest I could find
For example, there is nothing to stop you in the UK buying a load of asbestos from a country that sells it and then selling it on to a country that has no ban, reaping a profit that you can enjoy in the UK with no law broken. Similar happens all the time.
In fact we have individuals and companies who grow cannabis elsewhere and sell it elsewhere, all legally.
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