The problem being if you try charge 25 quid for a game against PAOK you'll get no more than 15,000 in the Aviva. If you're charging €15 you could get 25,000 and potentially more in the ground. I don't know about you, but I'd much rather make the same amount of money and have 10,000 more people in the ground creating a better atmosphere and not making the league look like a bunch of fools in a 1/4 full stadium.
I'm sorry for trying to use logic. I know it's not entirely welcome here.