Fallacy:
(Often with firearms, or firearms of a type, a magazine of a particular size, etc.)
E.g., "Why do you need a 30-round magazine anyway?"
Response:
Why do you need access to the Internet? You don't. Yet you have it anyway. Asserting "You do not need X" even if it is true (define "need"; need to live?) is not a justification for stealing or infringing a person's right to obtain or manufacture X.