You don't need to pay for an account to get unbanned. It depends on the moderator if you get the account back or not. Might want to tell us which is the account you are referring to? It's hard to guess what the problem might be.
Why are they then trying to charge me 0.25BTC for unbanning?
The fee was lowered to 0.1BTC because he's from Finnland, I could say that this is ridiculous.