OMG! Now that you said that, I remember my mom saying her mom did the exact same thing!!! They didn’t have much money growing up and at the end of the month it was Spam and potatoes.
Wow--I'm having a flashback, LOL! My grandma made the same thing. She would fry the Spam, then fry the potatoes in the Spam grease. Nothing was wasted :)
She made her own biscuits too--rolled the dough and everything. On Spam days, she would make Spam biscuits--MAN! Those were good :)