Heard the same rationale during the tech bubble. Bitcon is growing due to speculation, pure and simple. Those who got in early have ridden the bubble up, hopefully exiting before the burst, what you have now are all the fool lemmings following in their footsteps trying to make an easy buck only to watch their profits go bye bye.
On one level you are right, but on another you're missing the fact that there is more ways to profit than simply hoping value goes up. In fact, you could put yourself in a position to profit from a bubble burst as well if you use some imagination.