When you are searching for cases, you'll want to focus on the Uniform Commercial Code, which has been adopted in nearly every state in one form or another, and focus on Course of Dealing or Course of Conduct by the parties. What you'll be arguing is that there was a pattern of repetitive contracts between the parties that provided an implied contract that Company A would send Company B 1000 videos at periodic intervals. At a minimum, even if you lose the course of dealing argument, Company B either needs to return the videos or pay the standard price from prior contracts under the theory of quantum meruit or unjust enrichment. Both of those equitable theories prevent one party from receiving valuable goods or services from the other party without paying for them. To allow such conduct would be to allow Company B to be unjustly enriched by allowing them to keep a product without paying for it.

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