That is one of the reasons my kids have cell phones.
I remember way too vividly a time where I was at a friend's house and was not comfortable with the situation. My parents did all the right things by meeting the parents, etc, but you know the saying....behind closed doors...
I wanted to call home to have my parents come get me, but the Mom kept saying "oh, let's just go try it again.." and basically would not let me call home. As an adult now, I can reflect back that she probably took it personally that I wanted to go home and didn't want it to reflect badly on her.
One other time, I was at a party where drugs were brought out. I went upstairs to call home. Parents asked me why. I hemmed and hawed, not wanting to say "Uh, your daughter just pulled out the bong"
I vowed my kids would never be in that position where they would have to explain why they wanted to use the phone. Now they can quietly go to the bathroom and text me to come get them if they are EVER uncomfortable in a situation. Nobody has to know they texted. No conversation during a call to overhear.
I will show up with some excuse about a family thing and I am sorry but DD has to come home now.
That is a great reason. I hadn't thought about it, and told dh too.
Sometimes you just feel like they have everything known to mankind already, kwim? But you bring up a very compelling point.