Why would that happen? Car to explain this conclusion to me?
That will place the RI in breach of their Custom union with EU. It's like saying, RI currently importing goods from SA duty free, in breach of their custom union with the EU. It's not happening. If the RI "exports" to NI duty free they are in violation of their Custom agreement. The Belfast agreement stands, it's up to RI to abide by it in breach of their agreement with the EU or add duties to the goods in breach of the UK.
Let's look at the intricate part here between RI/NI.
The good Friday agreement makes provision for: each side to institute checks as required for security.
I recall a time RI themselves implemented a border with armed guards to stop cattle being moved between NI and RI with some foot and mouth outbreak. Ireland is playing politics here and the Bemoaners are falling for it hook line and sinker. A hard border between RI and NI will not be a breach of the agreement. The duty/duty free issue, is between EU and RI. From my understanding there are already different tariffs on things like fuel and cigarettes between NI and RI. So even duties/tariffs are not an issue.
Some please tell me how this is breaking the Belfast agreement?