Most people’s responsibilities rely on other people’s responsibilities, so when we tell ourselves “not my job” there’s almost always an “as long as they do what they’re supposed to” addendum.
If someone else doesn’t do it and it is a precursor for something you need than it is your job.
If the deli manager doesn’t do it and you still NEED cheese than you still need to get cheese. People are not taking the word need seriously enough ^_*