You're right about the clove hitch being less damaging to rope than many other knots, at least in many of it's applications. Some of that advantage can be lost, however, if the lead puts a sharp bend in the rope. The construction of the rope itself also affects the amount of damage from bends. Constructions where all of the fibers spiral are less subject to damage because a fiber goes only a short distance on the outside of a curve before passing to the inside of the curve. Tight curves offer less opportunity for such compensation than more gentle curves.
As I recall, The Ashley Book of Knots has some good information on this topic but I can't check because my son made off with my copy a decade or two ago.
In the case of hammock suspensions, one way to minimize damage is to take up much of the strain with friction between the line and the anchor. For example, a suspension line that first wraps around a large diameter anchor, such as a tree, for several turns and then ends with a clove hitch will suffer less damage than an arrangement where the entire load is taken by a knot. But it's more of a nuisance.