Do you think its pathetic people would call police on someone having sex with a 16 year old?

In a lot of places 16 is the age of consent. Mind your own business.

No absolutely not pathetic. I was sexually assaulted at 17 and it wasn't even full sex and I had no idea what was going on because I was so sheltered. So no. Look up laws before you do anything that could land you in prison forever. 

They have found Pornhub apps on the cell phones of kids in junior high.

Depends on the area. If that's the law, it's the law. If you don't like it, move to an area where it's acceptable. In established areas where it's not accepted, they have their reasons and you would have to take it to court to argue against all of them. But note, sounding angry and calling it "pathetic" will get you nowhere and they would only deem you as just an individual caught in their emotions.

They are, legally, minors. And 16 year olds are not famous for making good decisions for themselves. If that "someone" is 4 years or more the elder of that 16 year old... it's illegal even if consensual. No. I don't think it's pathetic at all. People prey on children who think they are "old enough". And hurt them.