It is actually bad for bitcoin as it takes away the decentralized part away from bitcoin. And it is hard to trust them as they might sell for fiat for their further investments.
This is what "bank" do to earn profit. They use our fundsthat we save to lend people with some huge interest or use the funds for trading to get more of it. Bank is designed to get money not to give free interest for everyone but I dont see why it taken the decentralized part away, so keeping bitcoin in one place is decentralized now?