You can't use unhashed passwords at a site, that deals with money. That's just one big mistake you just can't make if you want to make such a thing. What if someone hacks your database ? He could steal the money and BTC funded in all your users accounts.
That the variable coming to server is unhashed does not say that the DB uses unhashed pws.
The password is practically always transmitted cleartext to the server, within SSL session most of the time however, on crucial things. But it does not tell is it hashed in the database or not.
The thing about if the encryption is clientside, it's trivial for any hacker to hack as the algo can be trivially disassembled and disseminated.
It's a very bad idea to transmit the password in GET variable tho.