My God! What a nonsense! Lourdes is a typical pilgrimage site for Roman Catholics.
Ya but Lourdes airport has a catchment area similar to Shannon airport.
Ok, the airport happens to be near a pilgrimage site, and they have rightly taken avantage of that in the naming the airport, but this Stansted route will appeal to some French in the
region wanting to visit London (or chance their arm with a connection to another Stansted route). Ex-pats on both ends of the route will naturally be potential customers as well, and then there are the Brits in and around London who'll want to visit the Lourdes*, the surrounding region, the Pyrenees and the
ski resorts. Ya, infact with a 1 x weekly frequency on Saturdays in winter, this is effectively a ski-route in Ryanair's eyes.
*The Lourdes season runs from Easter to end October (roughly), with maybe a bit of activity on Saint Bernedette's day (February) and the start of Lent. But mainly for winter the whole place is a ghost town.