You could simply make zoomed copies of selected sections of a store bought map. Would be a pain in the neck if you need new maps frequently.
Yes, and I’ve not seen maps in stores that have the detail I want. That’s not to say they don’t exist - maybe they are in bookstores? - but, that’s pretty inconvenient, as you say.
A big advantage of many of the big name online maps is the ability to quickly map out a route of, say, 500 miles, and then zoom in to any point on that route with a scale of, say, 1 inch = 20 ft. on a typical computer monitor, and ALSO include local landmarks.