Let's be realistic here, it's a combination of procrastination/annoyance/apathy. First you actually need to have snow tires, which today are going to cost over $1000. Then you need to schedule to bring them in, spending a few hours getting it done, all while paying more money. And then you're going to have to do it all over again in the spring to change back. Finally there's also the question of storage.
When most years in Vancouver it's not even going to snow, unless you're actively going up the mountains it's kind of hard to justify snow tires. And if some snow does hit the forecast, good look getting an appointment. From what I recall last time I did it try to book an appointment to get your tires changed now and you're probably looking at a wait list of a few weeks.
It's one thing if it was a fact of life like most of the rest of Canada but Vancouver it's just a huge pain, sucks if people get stuck driving in the snow when they're not prepared for it but I don't really see what you can do about it. Don't look at me though I grew up in Northern BC, driving in snow is something we did for fun as teenagers. I'd second what someone else said the importance of taking a kid learning to drive up to an empty parking lot with snow and letting them have some fun.