Nobody has shown that what Apple has done shouldn't be morally acceptable.
I know I'll regret responding to such an obvious troll, but...
1) When a company like Apple avoids/evades paying taxes, it hurts the free market by taking for themselves an advantage that other companies can or do not. Primarily, a company the size of Apple does this by using its tax advantage to press anti-competitive advantages by buying up other companies. If you or I wanted to buy a company that Apple also wanted to buy, and the company cost $1billion, Apple would basically be able to buy that company for $700million while we would have to pay the full $1billion. By using this advantage to destroy competition, there is greater consolidation and greater loss of competition. Pretty soon, it's not really a market at all, much less free.
If you believe a "free market" is a force for good, then what Apple is doing is bad.
2) By not contributing their share of taxes (the same share that other companies have to pay), Apple uses public assets without paying for them, forcing the shortfall onto the rest of us and their competitors. Bad for us, and bad for the free market.
3) Stealing is immoral. Even you would probably agree that taking something that you have not paid for is immoral. Apple uses a lot of common resources, from infrastructure to the legal system, at a much higher rate than most people (or companies) by not paying their share of the costs, those costs are shifted on to us. In the language of the American Right, Apple is "stealing from future generations".
4) Lying is immoral. Here's one of Apple's tax "avoidance" scams: They register a patent in the United States. This forces the United States government to use resources to protect Apple's patent rights. Then, Apple transfers the ownership of that patent to a company that does not exist in Ireland, which pays its fees to another company that does not exist in say, Holland (thus the famous "Dutch-Irish Sandwich"). Because the ownership of that patent is in the other country and removed further by paying license fees in the third country, Apple completely avoids any taxes at all. Yet, if an Apple patent is threatened, they sue in US court and the US government is called upon to protect Apple's patent. So, for the purposes of taxes, the patent is not American, but for the purposes of enforcement, the patent is American. I'm pretty sure you can see how this is immoral.
Further, I'm betting that Apple's claim that 2/3 of their profits come from outside the US and indeed outside the jurisdiction of any sovereign nation, Apple's lying. This is why they're going to settle this ASAP, because if the forensic accountants go to work on Apple's books, the penalties could be astronomical and Apple's already wounded share price would halve again.
5, 6 & 7: Corporations were given special status to protect investors and owners from direct liability, not to protect them from having to act in a moral way. You seem willing to absolve Apple from any moral responsibility for anything, yet you want them to be treated as a person for the purposes of political activities. So now the moral questions are directed at you, khallow.
Finally, if you believe that taxes are immoral on their face, I would remind you that the purpose of the American Revolution was not to achieve freedom from taxation, but rather from taxation without representation. You cannot make a persuasive argument that you are not represented. You may not like your representation, but that's the way our system was designed. If you don't like the American system, then we have a different discussion altogether.