Cost

What supporting points could be made over allocation of indirect marketing costs,  by the proponents of each side, in the full-cost versus contribution-margin controversy ? Which of the two concepts do you advocate, and why?

Spiro, R. L., Rich, G. A., & Stanton, W. J. (2008). Management of a sales force (12th ed., Pg. 442-444). New York: McGraw-Hill/Irwin.