I know this one off the top of my head! I was there!
Seriously: why turn lead into gold instead of into a more useful metal like stainless steel?
It’s because (drum roll, please): Gold is an extremely useful metal because of one attribute — it is used as money! And if you can create money then you’re either a bank, a government or an alchemist.
So that’s the answer: gold and silver were used as money, with which you could buy whatever you want (including “love” and stronger metals).