Should you design a pension system for the people retiring there, or the half of percent of people who are visitors?
He is EU resident. Imagine in US you would be forced to contribute to state pension, but would get your money only if you work for 30 years in single state. Moving from California to Texas == zero pension.
I do however find it strange that he's not entitled to a pension he paid for. I guess the EU isn't ready for that yet.