I am also an apple investor. If they have $50B of cash they have no use for, then they are forcing me to be invested in government bonds. I'd rather have the money myself, and invest it in something that gets better than a .5% annual return. Using the dividend to buy more Apple stock would be better than the current situation.
They don't need those for immediate ops right now, but having tens of billions readily available is a great chip when discussing deal with manufacturers. It means you're able to put billions on the table upfront at a financial moment's notice. Apple's billions in the bank are a major asset in their negotiations.
I wasn't stretching anything. Tim Cook said Apple has "more than we need to run the company." Running the company requires having cash for immediate, future, foreseeable and non-foreseeable events. "More than we need" means there is some that there is no need, or "no use".