Why moral imperative? Perhaps you mean ethical or legal, but is not even legally required, so far as I know, that a corporation must maximize return to investors.
More broadly, society created the concept of the corporation and imbued it with valuable privileges such as limited liability and a potentially favorable tax regime. Some argue it would be morally reasonable to require it balance the interests of stakeholders.
Evasion is a bug in the tax code. Avoidance is a feature. Laws are written to create the possibility of avoidance - e.g. we add a 20% tax on cigarettes. We create a 20% tax credit on solar panels. We don't tax interest gains off of savings accounts.
For what it's worth it's pointless to complain about tax law complexity. Complexity increases with the amount of money you're trying to drag out of the economy. The more money you want the greater the temptation to create loopholes because they end up being worth more. Imagine a country where the tax rate is 100%. If you pass a law that taxes building cars at 90% you've effectively created an industry. Compare that with how much you'll be loved if the tax rate is 10% and you lower the tax on making cars to 9%. Still good but you'll only garner like not love.
Honestly this is why the details of tax law - how fair it is for example - only marginally interest me. The overall rate - and for that you might as well include borrowing, so it's easier to just ask - what percentage of GDP does the government spend are a lot more interesting to me.
not a judgement call, just not sure how you frame the raison d'etre for something that oesn't embody life to begin with.