I would say the other POI markers do serve one value, and that is with regards to finding a place... if you notice it's right behind the McDonalds, then you know you are close when you see the big M from the street. Similar for strip malls.
That's true, but it's not Google's intent. It's just another source of ad/promotional revenue. The POIs show up before I search anything. A more user focused solution would wait until I selected a destination, detect that where I'm going is a less frequented, and then display something along the lines of "Hey it looks like this location can be difficult to find, here's some near by stores to look for <insert recognizable brands>."
