actually, one reason is, like u said, simply becos it can get
too relaxing to drive an auto car, and becoome careless. Also, it
can be easy to forget to step on the brakes while the car is
stationary, instead of holding the clutch in in a manual car.
as for the accident u witnessed, well, civics are known to have
softer body panels. pickups are made of tougher steel or other
materials. sometimes, the aftermath of an accident can be deceiving
as to the speed of impact. what looks bad may have actually
happened at low speeds, or vice versa. of course, if the car is a
total write off, that high speed was involved is in no doubt. For
the civic, unless u actually witnessed it, u can't be sure. it
could be that the pickup jammed brakes and the civic was
tailgating, it could be other scenarios. we don't know for
sure.