Would it be legal to use Cott-produced, generic beverages in a film?
I received an answer from an actual lawyer:


  Context matters. As a general matter, it is perfectly "legal" to use anyone's logo or brand indicia in a film, without permission, as long as it is done in a manner which does not falsely suggest the endorsement or sponsorship of the film or the producer's products by the trademark owner. For example, it is entirely possible to have your hero drink Beefeater or 7-Up in clearly identified containers. No permission is required. It is not really clear what interest you may think is being protected, but trademark law doesn't preclude all use of the trademark owner's mark by others. Sometimes, in an excess of caution, such permissions will be sought. They are nearly universally granted.


From Hilary B. Miller on Lawyers.com