If someone makes their own plow, it immediately has a "cutting edge". The actual plow blade becomes the cutting edge. But who wants to wear down their plow blade? In order to solve that problem, a replaceable plow edge was added, which we now call a "cutting edge". Cutting edges are there to protect the actual plow from wear and are therefore a disposable item. The skid shoes are there to solve a different problem. Plow damage.
One of the major problems encountered while plowing snow is the risk of bending or breaking the plow blade or the plow's harness. This damage can occur due to frost heaving of surface being plowed or from catch basins and manhole covers sitting higher than the roadway. The ski's allow the Operator to lift the cutting edge off the road surface in the hopes that it will pass over such obstacles damage-free. When plowing surfaces that are not paved, the ski's minimize the amount of road surface that is picked up the the plow. The Case and Ingersoll blades are equipped with a "trip feature" to help protect them from damage but you must remove the "trip pin" to enable this function and make the blade spring loaded.
To me, it all comes down to KNOWING the area you intend to plow and to deal with potential hazards to your plow long before winter sets in. If you have a gravel driveway, then regrade that driveway and make it as flat as possible. Set the ski's a half-inch or even one-inch lower than the cutting edge and don't sweat the snow that is left behind during plowing. If your driveway has a paved surface with curbing, then drive T-bars or wood stakes into the ground alongside the curbing and especially at any corners so that you know where the curbing is located even when it's covered by a foot of snow.
Ramming into hidden items can produce hidden damage to your lift cylinder, the anchor for the cylinder and all of the linkage between the cylinder's rod and the bell-crank that lifts the blade. You can also bend up your Snap Fast mount system and that will affect how well your deck cuts the grass next season. Plowing in Hi-Range and changing direction without coming to a gradual stop can cause the dreaded bolt breakage in the trans-axle and this is more pronounced if loaded tires, wheel weights etc are used.
If your driveway is free of any obstructions that would catch the edge of the plow, then there is no real need for the ski's or shoes. The cutting edge is there to clean the snow off the driveway all the way down to bare pavement. Don't worry about the wear on the edge. It's supposed to wear. Just keep an eye on that edge and replace it before the pavement can start wearing the actual plow.