or let's say, marriage to canadian citizen. It is a CRIME in canada to marry canadian citizen for the only purpose to get the immigrant status. Now. you can say. Marriage is legal? yes. Visa is legal? yes. And still, once it's proved that the reason was to gain entry into Canada only, visa will be revoked. Even a CITIZENSHIP itself can be cancelled as per recent law, if it's proved that it was obtained in illegal way.
there is nothing to argue about.