I bumped into a lady in the ILAC centre on Saturday. She was from Dundalk and had got up at the crack of dawn to travel to Dublin to do her Christmas shopping. On principle she wouldn't shop in the North as she believed money should be kept in the South. I had to admire her stance.
I think she is a reflection of why our prices are so high in the first place - we have been happy to rip ourselves off for years.
The VAT difference is only 6.5%, apart from that most of the rest is just ripoff margin. A lot of goods come from China, USA and mainland Europe etc. so the final prices should be similar except for the VAT.