I gotta say, I don't think it's really that necessary.

You can always catch a bus back to Dublin in a few hours, it's a pretty small country as you know. In a true disaster I'm sure you can somehow catch a ride to a population center and therefore to a Dublin bus.

I'm not sure what "righteousness" you're talking about, to me it's more that it's rather inefficient. Rather than ride from one city to the next, it sounds like he's going to do relatively small loops every day. So he'll lose hours every day driving and dealing with the car.

Even carrying gear it's much better use of your time to just throw your gear on the bike and go from one town to the next, you'll see a lot more of the countryside that way.