Because dishwashing liquid uses lemon oil, while lemonade uses lemon juice, which spoils.
Snappy answer now heres another question: What lemons does GM use to build their cars?
Oh, they bought the entire supply when Nash-Rambler went out of business.
I would say Nash Rambler was the better car company.
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them