It's for your company's protection, and for your own, and you should be very grateful for that policy.
It greatly reduces the chance of you being accused of sexual improprieties with whomever you're ejecting, who probably isn't very happy with you and probably realizes that your being accused of putting your hand inside her shirt is going to be far more of a headache for you than her. True or not, you'd probably get fired so that the company wouldn't get sued on the basis of "tolerating a culture of sexual harassment by male employees", or something like that.
And, believe me, you do NOT want to have your name in the local papers being accused of shoving your hand down the pants of a fifteen-year-old girl, even if the story is obviously ludicrous, because your next employer will probably see the article and decide that the other guy applying for the job, with a resume that is ALMOST as impressive as yours and has never been accused of fondling a girl the age of this guy's granddaughter, will be a better fit for the job than you will be.
You also don't want to defend from those charges in civil or criminal court. And you REALLY do not want to be on a sex offender registry somewhere. Or serving a prison sentence for a sex crime, especially against a minor (a lot of those large men with arms the size of your legs and a history of violent crime longer than a russian novel have daughters on the outside, whom they're currently helpless to protect...).
This way, if there's any question, the female coworker pipes up and says "Nah, he didn't do anything REMOTELY out of line. That girl is so full of shit that it's leaking out of her ears", and your butt is covered (and still employed).
Now the company most likely couldn't care less about you, but this reduces the chance of a lawsuit. And, if you ARE a pedophile (or ephebophile, if we're talking about teenagers), this makes it less likely that you can molest a kid even if you are a predator who managed to get past whatever screening process your company has.