Which would be fine if there were EU regulations about taxation. Now it's just multinationals playing out different EU members against each other to get the bes

Which would be fine if there were EU regulations about taxation. Now it's just multinationals playing out different EU members against each other to get the best deal, look at Ireland and Luxembourg. I can imagine a EU fiscal policy would be heavily lobbied against by the companies that use these back doors, as it would shift power back to the politicians/people: either you have access to the EU market and pay taxes according to these rules, or you can't sell your product here.