[lotharbot]

> "they're old and trying to apply old customs to new situations"

I doubt it was seniors who came up with the phone-stack, and it's definitely not seniors who have spread the idea on social media. I see it spread by 20-somethings and even teens who are sick of people being rude by ignoring them.

It might be different if it was used to signal disinterest, when someone is just droning on and on. But people dive into facebook/texts/whatever on their phones even when they're interested in the conversation, and even when the person speaking has barely started. It's like a compulsion. A rude compulsion.