...you, maybe? Chances are you aren't one of those people who still has a pager. But they actually still exist. Via Randy McDonald here's a CBC article on the persistence of pagers in Canada. They're primarily used by those in emergency services and medical personnel, as they're perceived to be more reliable in certain conditions. However Telus has announced it will end its pager service, and industry watchers figure the other providers in Canada will follow suit.
I can't think of the last time I heard a beeping pager. Perhaps if I lived in a more rural area, or spent a lot of time around someone in medicine, I might be more likely to hear one.