I very much think that's the wrong lesson to learn from people's willingness to fork over $100/mo for pay TV.
It is not an iron law that people will not pay $8 for apps because less than $8 is what apps cost, and $8 is what beer costs, and $100 is what pay TV costs.
It is a law, I believe called "gravity", that products that present themselves as market substitutes for other products that cost $1 will have a hard time selling for $8. This does mean that, absent a very effective and inventive marketing strategy, casual games and offline web page readers are hard to sell for $8.
Then the logic question as far as the OP's original topic is this:
Can any app truly be a substitute good for a sweetened beverage with stimulants in it? I would say no. It doesn't matter how much people are willing to spend at Starbucks. It has virtually no bearing on how they'll value your app.
It is not an iron law that people will not pay $8 for apps because less than $8 is what apps cost, and $8 is what beer costs, and $100 is what pay TV costs.
It is a law, I believe called "gravity", that products that present themselves as market substitutes for other products that cost $1 will have a hard time selling for $8. This does mean that, absent a very effective and inventive marketing strategy, casual games and offline web page readers are hard to sell for $8.