I have to agree with Turtle, It is not a necessity, but nice when needed, like in bad weather and road conditions, or when you may even pass by a friend of yours that also may have a C.B. in their van.Believe it or not, but a P.A. speaker also may have it's advantages as well, especially when an undesirable person may come knocking on you're door at night.The last thing they want is more attention drawn to them by you're van.
I have noticed, as time goes on, that more and more drivers are not talking on the C.B. like they used to, being in part due to XM radio, cell phones, etc, to keep them more occupied throughout the trip.It used to be where you couldn't get a word in edgewise, but now, it gets pretty quiet out there..