So when people agree with the EU findings on this subject, it isn't just out of spite or dislike of Apple. Some feel strongly about tax evasion, as it enriches those who practice it to the detriment of ordinary citizens (taxes pay for public works and institutions). Some may find that huge corporations benefit unfairly from these convoluted tax evasion schemes compared to ordinary citizens, and small and medium sized corporations, and they seem to get away with it too (unfair competition).
Apple knew they could get caught, that risk has been assessed when they implement this scheme and found to be low enough to warrant it at the time. If anyone else gets caught not paying their dues in taxes, you can bet the local revenue service will be knocking on your door for the amount owed. Corporations are no different.
Also this isn't just about Apple. The EU has been going after a bunch of mega-corps the past year, including Starbucks. Apple is just one of the bigger fish amongst the big fish.
And, I'll leave aside moral considerations because they are not strictly relevant to the point of whether the EU's ruling is correct.
My point was that I don't see that either side of the legal argument is blindingly compelling. Certainly not without hearing a lot more argument and research from both sides.
It comes down to a disagreement over whether Apple's use of a particular loophole in Irish law constitutes Ireland giving Apple a special deal that is unavailable to other companies.
Apple/Ireland argue that the loophole existed in law and was available to anybody.
EU argues that even though the loophole may technically have existed in Irish law, it still constitutes a special deal with Apple because (I think) it takes a lot of money to hire the tax experts necessary to exploit it.
What is the knockdown blow that makes either one of these either totally compelling or totally uncompelling?
I don't see why people are so certain on either side of this.