I think they are still believe on what bitcoin can do so they are still but more BTC because bitcoin price is so unpredictable, i hope to that bitcoin will go again into his highest value like on december 2017 many of traders and BTC holder are so happy when bitcoin pump on 1btc = 1million.
Yes, some of the people who still buy bitcoin is the people who believe in what bitcoin can do in the future even though the price of bitcoin now are drop. We know it can recover.