The two rulesets are following different ethical norms.
The difference with taxes is that there isn't some well-agreed upon precise amount or percentage of money that companies are supposed to pay. The rules are very complicated, even for companies that most people wouldn't consider to be "searching for loopholes."
In other words, it may be easy to get a lot of people to agree that Apple should be paying more taxes to the US, but how will they agree on an exact amount?
So a 2in x 11ft fuel line was "too far".
But what about a 1in x 6ft fuel line?
0.75in x 3ft?
Which of these is not too far?
> specifications for fuel lines were created immediately
It sounds like everyone recognized there was underspecification and it was remedied.
Are you suggesting that was wrong?
Instead of a half-inch fuel line, Yunick created a two-inch fuel line that was 11 feet long, and held five gallons of gas.
(A car with more gas has to stop less often)
You could say he took a loophole. You could try, I'm sure, to argue "how could he have known he wasn't supposed to make a fuel line that way? What was the correct ethical size of a fuel line?". But it's pretty obvious to most people that took it too far, and specifications for fuel lines were created immediately after the gambit was discovered.