I assume that any pub selling crisps and nuts will have to ban smoking, which is almost all of them :-))
I reckon the cowards didn't want to lose votes in the north which is their votes stronghold by putting a full ban in place. It works very well in Ireland so why not here? Some pubs in Ireland have created the most imaginative ares for smokers in gardens and courtyards so their smokers can legally stay on the premises and not clog up the doorways to the streets.