It totally makes sense. You have thousands of fit (thus mostly better-looking than the average) and healthy 16-18 years old reunited in 1 place without parents. Of course many will want to have sex and they will. So it's a good thing the IOC helps to make it safe.
I went to a similar event (but Europeans only) when I was 16. We were there for 10 days, I had only 2 races to do and they were on days 2 and 4. So plenty of time to meet people, go cheering the tennis players and the handball teams of my country (those 2 sports were taking place right next to the track). All athletes were sleeping at the same college campus (it was end July so the college students were not there). We also had a cultural journey all athletes together and they organized a huge party for us. Obviously there was a lot of flirting going on, amongst athletes of the same country but different sports as well as between athletes from different countries. Definitely one of the 2 periods of my life where I witnessed the most casual sex (the other one being my year as an exchange student).
I have great memories of that event ; the races themselves, the good atmosphere, that hot French soccer player I dated for some days and the friends I made there (18 years later, I am still good friend with 3 of the handballers I met there).
I wish all those guys and girls to enjoy the competition (take it seriously and give their best) as well as the experience as a whole (travelling in a national team, meet people from different sports and cultures and, if they want, the safe sexual encounters).