I think you are looking for Chauvinism:
a form of extreme patriotism and nationalism, a fervent faith in
national excellence and glory. It is an irrational belief in the
superiority or dominance of one's own group or people, who are seen as
strong and virtuous, while others are considered weak or unworthy.
A less strong but still apt term is Nationalism
As no one has posted a better answer and the question is still open I'm going to elevate my comment to an answer.
"Subsistence expenses" is quite a common term for this. It has the advantage that it covers not just formal meals but also drinks, snacks and sandwiches on the go.