you were right, if they really think btc going to da moon. they should buy btc more, not lend btc for peanut. unless they were whale and they lending btc at peanut rates so everyone can short btc and keep the price low
Actually, you are very wrong here. Warren Buffett made the same point about those who short the stocks that he owns: he loves it, and loves to lend them stock so that they can sell more. Why? Because he wants to buy more, as cheaply as he can. The shorts pay him interest, and pressure the stock so that he can load up at a more attractive price.
Similarly BTC accumulators - those who are buyiing btc consistently - would like to see btc price stay 'low' for as long as possible, in order that they have enough time to accumulate as much as they can, as cheaply as they can. I'm somewhat in that boat, preffering that we maintain low prices for an extended period while I continue to accumulate. If btc price rockets tomorrow, sadly i will not have bought enough!