Some people are interested in the rising price, some people are interested in the interesting things that can be built with and/or on top of it, and some people are interested in some other aspect of the technology that has sprung up around it.
Before you get too gleeful though, I would wager only a small percentage of people who have ever bought Bitcoins have sustained a loss as of today. Besides, there's nothing wrong with putting money behind a technology and then reaping either a gain or a loss based on how successful it becomes.
My actual point was that you can't look at what the fee structure / usability / etc is today and conclude there's nothing useful there.
This is especially true with the more common argument of, "Sure, I can see why someone would find it mildly useful for use a, b, or c; but I don't think it's useful today for more mainstream purpose x, y, or z, so I think it's worthless." Especially when (so far) the abc list keeps growing and the xyz list keeps shrinking. I'm not sure where that trajectory ends, but I personally think there's a lot of interesting problems that will be solved with crypto-currency.