So picture this scenario: You're section-hiking the AT one chilly March morning, well north of the NOBO crowd. There aren't a lot of other people on the trail in that particular section. You're on a stretch of trail with a sharp drop-off to one side. You put your foot down on what you think is dirt, but it proves to be a sheet of dark ice... and suddenly you find yourself rolling and tumbling down the mountainside. A couple of hundred feet later, you land with a thud against a tree trunk and realize that you've broken a leg and a couple of ribs. In shock, drifting in and out of consciousness, you are vaguely aware that you're out of sight from the trail, that there's nobody up there right now anyway, and that if you pass out you're likely to die of hypothermia before anyone even realizes you're missing.
However well-prepared you are, this could happen. If it does, your first aid kit isn't going to do you much good. Your other gear can help stave off the cold (assuming your pack didn't fall off as you tumbled), but it's going to take the help of someone else to get you out of this mess. If you've got a locator beacon, this is the time to use it. It's more responsible to tell the authorities exactly where you are so they can come get you out, than to let searchers spend hours or days (and lots of money) combing the woods in all the places you might be.
You may feel that scenarios like this are too unlikely to justify carrying the weight (or paying the price) for this device, or a cell phone or whatever. That's a personal choice, and certainly you have the right to make it. My point is just that people who choose to get one can have a legitimate reason for doing so. Even if you think their fear is overblown, they have the right to make their own risk assessment. And one of these days one of them might just find you lying by the trail with a broken leg and summon help for you.I'm betting you won't complain or tell them not to bother.
Cell-phone haters must admit that this device is much more discreet and unlikely to bother other hikers...