what makes you think they made money? That's the basis of the rest of your post.
Because I don't see IE paying the NTA money to run a service which is loss making. If they don't make money then why not run more services? They have previously scrapped some late night Galway services because of even lower loading after some sporting events and if money wasn't the main aim then why not let pass holders on them?
The 2 Bruce Springsteen services were either sold out or had a handful of seats left and even operated with larger trains.