Costco (and perhaps other mass marketers) sells many DVDs in plastic packages, two or more "unrelated" DVDs per package. Why do they do this? I could understand if they packaged a "turkey" with a good film: this would give them more sales of the turkey. But the other day I picked up a package with two of Fox's war films in it, Von Ryan's Express and Twelve O'clock High, for $24. Each of these is a first rate film on its own merits. To get them for $12 each is a deal, as they sell on-line for at least $14 each. Costco could have just set them out individually and charged $14 or $15 for them. And the use of the plastic packages greatly increases the floor space required: these are those large hard-plastic jobs measuring about 12" by 18" and approx. 5" deep. What's the marketing advantage of Costco's doing this?