Oanda spreads are very variable and can be widened very oftenly sometimes(5 pips or more).And also they widened spreads in every Asian sessions consistently(1.2 to 2 pips) ... So their average spreads are much more than 1 pips if you get average of ...
You say that when market is not in anormal conditions Brokers cost for EURUSD is 0(zero) pips.If it is like that then they can offer 1 pip fixed spread and still can earn money.But I see most of ECN broker average spread over 1 pip and they still ...