Ugh... I'm with you Ron. I'll admit, when I saw the title of the thread, I was steeling myself to read yet another boring "Why can't I use my cellphone, I'm important, don't they know it's safe" DYKWIA style rant...
But that's not what you're saying. That's lousy customer-facing interaction, and I'll even concede it's probably not malicious. It's just poor training or self-awareness.
United used to have a Customer Service VP with a Disney background. They could really use her back.