- I am not sure where you got the idea of 1% fee in p2pool. But if you check the coinbase transactions in p2pool mined block, you can look for yourself that it is not so.
Well if there is an optional parameter that defaults to giving the author 1% of each found block....idk.. i would call that not free
When averaged in with the probability you will get the 1% yourself, it comes out to free.
Put another way, p2pool isolates you from 99% of your variance instead of 100%... Still pretty good if you ask me.