In fact, I think the last time I was at a cafe, was a business meeting where I was talking to a potential investor in an app I wrote. I clearly remember him telling me "Gosh, NO ONE wants to pay $2 for an app (that I had sunk several hundred hours programming into) these days...." while literally holding a $5 latte in his hand, and signalling the waiter for another.
What happens when you get caught up talking to someone or distracted, and your $4 cup of coffee becomes cold and undrinkable? Or if someone nudges you and you spill some? Does the $ value ever factor into it, or is it just a 'throwaway' cost?
In fact, does anyone ever stand at a urinal and think to themselves - "That is a $10 pee, given the coffees I bought this morning"?
"You don't buy beer, you rent it."
I guess the same applies to coffee.
Even the best apps have two unknowns - 1) you don't know if it's going to be useful, and 2) you don't know how to use that app; you need to learn how it works. The former issue can be obviated by word-of-mouth praise, but it's soooo tough to get over the latter.
Like you I am a startup founder, which probably means that we are both pathological novelty-seekers when it comes to tech. And yet... I worked at an amazing B2C startup for two years and, to be completely honest, I never really got into the habit of using the product daily. The app is targeted at my demo and I didn't use it daily.
That's why they say that the crux of building a great B2C company (e.g. an app) lies in changing the public's consumption habits. It's tough, and it seems like such an impenetrable problem. I have a lot of admiration for B2C founders.