It would be NICE of us to do so and I hope things do get sorted without having to put up a load of expensive and unsettling control points, but the onus isn't on us to make sure someone else's ideals are satisfied, only our own. The EU plans that would effectively mean Northern Ireland will be part of the EU and we can't trade with ourselves are ridiculous, and if they're going to make such demands then it's really just insulting to the entire process of negotiation