Yes, I have OCD about that. Even if it smells good and looks fresh, if it is a DAY after the expiration date. In the trash it goes. I catch hell from my mom alot of times because of it.
Anything beyond like 5 to 7 days, it just depends on how perserved it was kept. Like was it sealed properly? If so, then it may be fine. But anything after 7 is no.
Like I have had Yogurt after a few days it expired and it was perfectly fine...