Norms that are not strictly enforced, such as etiquette in the cafeteria and the dress code for class, are referred to as:

Norms that are not strictly enforced, such as etiquette in the cafeteria and the dress code for class, are referred to as: Folkways
Folkways consist of several set of conducts that seemed as appropriate or polite to do in a culture.Since it's not strictly enforced, folways do not have any form of formal punishment if a peson failed to do it