That depends a lot on where you drive. I've been in situations where, if I had hit a moose, there would have been no one around to call for help except the moose (assuming it had survived the collision, but they often do if it's a smaller vehicle). That stretch of road didn't get many passers-by on snowy Sunday nights in January. Maybe a half-dozen vehicles an hour. Combine that with poor visibility, and it could have been a long time before someone noticed and called for help. Fortunately, I never did have an accident along that stretch.
Of course, if you're only driving in built-up areas or along major transit corridors instead of in awkward parts of northern Ontario in the middle of winter, your chances of having someone call in for you are much higher.