Having thought about this idea in the past, I can say that one of the difficulty lies in the fact that the market "seems" really large, when in fact, you can on

Having thought about this idea in the past, I can say that one of the difficulty lies in the fact that the market "seems" really large, when in fact, you can only address a limited portion of it. People have different tastes and goals in what they want to accomplish in a "trip", and because the market seems so vast and large, the idea tends to gravitate towards the middle ground. You might satisfy a wide array of people, but none of them will really "love" your product. So rather than daily usage, I think the problem is of segmentation first (and competition, etc following...).