True! But most of them are chemical products, and will probably still be good after I have been dead and buried for long enough that my kids will have forgetten where the cemetery is… Even for biological products like antibiotics, which I am more hesitant to use when expired, a good doctor friend of mine who has served in many places of Asia and Africa with Medecins Sans Frontieres tells me that he has used antibiotics expired for many years with hardly any problem (not quite zero though).
Btw, the reason for his sometimes using expired medicine is when they use local government stockpiles that have sometimes not been renewed since colonial times…