Originally Posted by
EI-A330-300
The ticket couldn't of been protected as they do not allow short haul to short haul bookings. It appears to be like a goodwill gesture....
It was not a goodwill gesture, that would totally undermine the bread and butter point to point operation of EI, as you say tickets eligible for through check in are not readily available for purchase on their website. However they can be created by any TA with a GDS and many airlines interline with Aer Lingus in exactly that fashion. You can also achieve the same by booking a multi city itinerary on the EI website.
Lots of big hubs require a security clearance even if just transiting. As for the setup been ideal of not, transit numbers are growing strongly. The DUB-HUB signage is a smartphone device to guide transfer passengers.
Dublin is the only major airport I've used with a system that makes its transit pax effectively exit the terminal and end up at the check in desks in order to get their next flight.
As you have mentioned this is at least partially due to immigration regulations but still.