I don't understand how exactly the client forces the fee. I set paytxfee=0.00 in the config. Then I have launched bitcoind without args, sent a little amount to myself and saw 0.0005 BTC fee though I explicitly set 0.00 (or should I add zeroes and make it 0.0000?). Then I've restarted the daemon with the option -addnode=173.242.112.53 And my next tx has gone without the fee. Is the client somehow negotiate to its peers about the fee and forces 0.0005 if no one accepts free tx? Isn't it wrong? If I want not to pay the fee the client should notify me that no peers accept the free tx instead of silently wasting my money (yes, it's less than 1 cent but anyway it's money).
As I see on the block explorer most of txs are done without fees so either the free transaction policy is very popular or there's a way to set really zero fee in the client and I'm doing something wrong. Please explain this.