The Simpsons brings real family concerns to an absurd animated world, grounding its goofy comedy with genuine problems like marital stress, work woes, and monetary problems. Homer Simpson's finances are often a central issue around which several Simpsons episodes have centered. But a keen fan theory correctly predicted the family is actually fairly well-off and never actually in need of additional cash. While this is true, thanks to a throwaway gag from the show's strongest season, Homer Simpson may not actually need Marge Simpson's secret nest egg to support the family.
Source：https://www.cbr.com/simpsons-fan-theory-homer-finances/
