I also rarely talk about religion, but since today's topic came up so I am going to share some thoughts.

In my religion, sexual relationships before marriage are illegal, and when my religion says that someone is doing something illegal, we should discourage the person/people who are doing so. We aren't capable enough to control everything, and in such a case, we should try to maintain distance and protect ourselves from their negative influence.
There are cultural differences; otherwise, such a thing would not be possible here, at least openly, that happens there.