No problem - the likes of Asda are shipping from Jersey and are not charging VAT on their prices. Being based in Ireland we are obliged to charge 21.5% VAT. Further details can be found here
The trade off however is that deliveries from Asda won't arrive until at least the following week and in some cases the week after and may be stopped by customs etc It's a bit fairer to compare us to the bricks and mortar stores over here for pre orders as in the vast majority of cases we deliver on or before release day having dispatched from Ireland.
A lot of people of course may prefer to wait for the delivery and save a few euro whilst others are happy to get the game at a competitive price. Our customer base is generally of the latter but maybe in this case with the possibillity of a €10.00 voucher to come with the game we might encourage those who would order of Asda etc to join in.