Actually price of ingredients to a film recipe are not significant in the finished product. (and this is true to any industrial product).
Bear in mind that you have to factor in every cost from the factory building to the electricity and wages for the workers plus the cost of research, maintenance and the like.
Add to this that film is a perishable product so when you make a batch, you have to keep it "fresh" until it is sold. This involves freezing which IMHO will be a big cost...
And last but not least, ads, sales people, transportation, seller margin, and so on...
In last the maker have to factor in the competition and price the product at a level the consumer can afford, make some benefit of it and be a bit cheaper than the competitors..
Where is the silver price in this ??????