This is a lighthearted, fun, brainstorm.
If a game turns out to be fun and in good order I care little if it has an opening cinematic movie. Though, maybe it is good marketing to include a cinematic.
Maybe others, that have a different type of evaluation process do care. Maybe they get a demo or video or other source of information and learn that there is not a cinematic and think that the game is TOO low budget and assume that it won't be a good game. Thus, maybe they don't buy it.
I know...it sounds silly. [8|] Is it? Tell me. [:D]
I HAVE noticed that many games, especially stratetgy games, that did include an opening cinematic movie did succeed to an extent compared to other games that did not inclue a cinematic. Often, the games that did not include a cinematic faded into even more obscurity.
Edit: LOL. Then, again... there are many games that did not become a success and did include a cinematic. One game is a very infamous one. It had quite a good cinematic.
So, in those examples of games that did include a cinematic and became obscure maybe it would be that it was a bad game...or poor marketing.