I load my canoes and rowboats in that way, but I find that dragging one end on the ground is not necessary. I carry the boat into position and set it down so that it ends up leaning against the roof rack (or whatever loading aid that you choose to use, such as a bathmat), then walk to the rear and simply lift that end off the ground. I have done this when solo-loading other people’s kayaks too. If you don’t drag the boat, there will be no scuffing, and lots of handy items can be used as padding for the end of the boat that contacts the ground. I’ve even used a spare shoe because it was handy, but a piece of carpet or a doormat makes a bigger target. If you find that the boat slips, choose a padding material that’s more grippy, or make a pad that has a shape that won’t let the boat slide free, or attach a stern line just for loading and hold it tight while you move from the boat’s center (your carrying position) to the rear.
Oh, I guess I should add that there is no reason to not use wheels. Sure, once you put one end up onto your rack, the boat will slip if you let go of it, so the solution is to not let go. Keep a grip on the boat as you walk to the rear to lift that end. I do this all the time when using a dolly on casters to carry one end of a boat while loading at home.
It so happens that the boat in that picture will usually not slip in that loading position when one end is on wheels, but every other boat I have will slip. For the other boats, I still use the wheels. I just don’t let go of the boat, and if necessary, it’s a simple matter of chocking the wheels with something before letting go.