Keep in mind that the "Use By Date" printed on many food products is a posting that was created by the US Government (and states such as California) for "Protection of the Population". A variety of organizational goals went into the "Eat By Dates".
I remember in the 1980's eating a bunch of "expired C-Rats" in the field because the Supply Pukes had been told to get rid of those Vietnam Era C-Rats. No one got sick and they remained tasty (C-rats are in Cans. MRE's are in plastic baggies with foiled packages for each product for those who never served in military. C-rats were the generation before MRE's.)