Minors or adults, this is a startling demonstration of psychopathy. It's one thing to spread fear for profit, it's a whole 'nother ball game to do it for fun.
Psychopathy? I think it's more likely an excess of free time and puberty boosting testosterone in young men. These are just inquisitive, snooping horny teenagers.
They're not just doing garden-variety spying - they're deliberating trying to cause fear in their subjects by broadcasting their own presence.
There's a pretty big difference between a peeping tom, and a peeping tom who then mails you pictures taken through your window. One has no sense of boundaries, the other is taking glee in others' suffering and fear.
I'm a lot more concerned about the latter group - the lack of empathy is disturbing.
This is the equivalent of saying 'boys will be boys'. Dismissing this kind of sexual coercion and spying as just natural behavior is hugely sexist and insulting to men and boys everywhere, let alone encourages this kind of treatment of women.