yes, i have thought of the days when the price of BTC will not be in the lead.
i guess what does it for me is that BTC is written in stone. no one can change the code for this badboy. so, in that sense it is like gold: it will always have a natural inherent value. while others might take the lead, like you are suggesting, BTC, in my opinion, will still be trusted.
like i said, because the programmer is no where to be found, we're stuck with BTC as is. it can never be manipulated. unless someone finds a way to hack it, or if the original programmer all of a sudden shows up and has the secret code to fidget with the whole thing.