Why should they?
The use the saws are designed for doesn't require any dawgs.
The saws are designed to cut wood. If you fell often enough, especially in awkward positions, and must cut timber to length without damaging it, having a pair of dogs comes in very handy on any saw for such work. If you are always square to the tree or standing, or cutting small trees and do not care about wood pull or having to meet your cuts or having to reach around the bole to finish or start a cut, then it doesn't really matter. If you do not cut professionally, or simply do not know how to use them, you need not worry about such things.