A common statement is which a person attempts to convey that "rules" (policies, laws, etc) must be followed
irrespective of personal
intuition or any sense of what really makes sense. "
Rules is rules" conveys that it is the rule, and nothing else, that determines a certain action or inaction. The statement is usually used in a context where it is believed that the rule "doesn't make sense", but it must be followed anyway, simply because it is a rule.
Unfortunately our company doesn't allow us to send
Excel files because they might have malicious
macros embedded. Even if I know an Excel files is safe, I can not send it to you via email because "rules is rules".