All kidding aside, there are other factors involved outside of releasing a demo. What do the samples consist of? Are your samples limited to the four games? If not, are you comparing the extreme maximums with the extreme minimums?
Honestly Tomb Raider would have been a new game purchase for me; but with no demo because it would "spoil the story" made me think that I was right to assume it was turned into an interactive corridor movie. A used game purchase later, I found that I kind of liked the game. Go figure...
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