Thats the thing
Alot of male idols have secret love children
Someone of them confess to having a family after their popularity has faded abit and just want to retire
It's a selfish male issue. They don't want to use condoms, and they know that realistically there are very few consequences for them* if a pregnancy happens. So there's not much chance of a change.
* Plus propaganda still circulates in Korea that you can only catch sexual diseases from a foreigner. This is why their sti rates are high.