If it were guaranteed that the price of bitcoin would stay the same as it is today, would you still buy it? My guess is, the answer is no. But if its value lies in being a currency, price stability is essential. And if your answer is no, how is it then not just a Ponzi scheme? In other words, everyone is buying it on the hope of someone paying more for it in the future, not to use it as a currency.
We all are here for the profit so my answer is no. Lots of investors put their money on it because of profit and besides the popularity of bitcoin and its acceptance would not be this great if its prices did not increase.