(i) There is a load of cross boarder smuggling due to differences in VAT and taxes. I believe that the different tax regimes makes booze cheaper in the North and fags cheaper in the South. There are also petrol price differences. Nobody gives a fuck. The issue is where intermediate goods need to cross the boarder to become final goods prior to either (i) being sold (ii) crossing the border again or (iii) being exported out of Ireland. A hard border will kill this and hence be a disaster for NI and a problem for Ireland. Most of Ulster’s exports are shipped out of Dublin, which will be fairly annoying.
(ii) The Irish Govt would prefer a border down the Irish Sea from an economic point of view as the business with the mainland is much more important than that with NI. There prospect of an upsurge in violence is what is the real concern. It has not totally calm up there t say the least. The latest stats are grim:
During 2016/17 there were 5 security related deaths, two more than occurred during previous year (2015/16). The number of shooting incidents increased from 36 to 61, however the number of bombing incidents nearly halved compared with 2015/16 (52 to 29). The number of casualties resulting from paramilitary style assaults increased slightly compared to 2015/16 (58 to 66), while the number of casualties resulting from paramilitary style shootings doubled from 14 to 28. Compared with the previous year, the quantity of explosives seized by the PSNI increased while the number of firearms and rounds of
ammunition seized decreased.
If you do look at that link, the figures in Annex 1 would be a good place to start if you want to understand why most people I know want the GFA maintained. The cessation of hostilities has been very good for people’s living standards which have yet to recover from 2008/9. The impact of the crisis was very severe in Ireland and NI in particular.