Question

In 1957, james vicary reported that subliminal messages in a movie reel ("eat popcorn") caused viewers to rush to the concessions stands. although his findings became famous, the problem is that

Answer 1

In the movie the phrase "eat popcorn" can be recorded backwards or be hidden into the lines of characters or in the music. So yes this is possible that there was a subliminal message telling the viewers to buy more popcorn.