The grid place drop thing is totally irrelevant for the back of the field as well. If you are in a Sauber or Manor, other than having no money, there really is nothing stopping you from taking a new engine and gearbox every race. This penalty system only really punishes the people fighting for the championship. Which is mad, do we really want a championship decided because someone ran out of engines.
There has to be a better solution than penalty grid drops. Maybe removing constructors points. I don't think fines are the solution either, that just benefits the big teams who can easily afford it and could finish off the struggling teams further down the grid.