GAON (= never having heard of Rashi or Tosafot), if they do not know the “how to” and they will attempt to defraud the government he is helping them to do an aveira.
Joseph, according to the statutes I cited they are considered like married people for the purpose of benefits. while they cannot say that they are married they can claim to be a couple.
CTL, I doubt that anyone memorized the statute book. In fact, when I cited a statute in a case before the President of the Jerusalem District Labor Court (appealing a National Insurance Institute ruling) he had to look it up as it is not a well-known loophole (I checked the law on the Internet as I had once seen something that suggested it).