Most pools (not all) got an early advantage when there were no fee free options other than solo mining. And since they got an early advantage, they have size and therefor less variance. So, people pay a fee for less variance. Also simplicity.
Seems silly to me, yet look at the size of the fee pools.
Options like P2Pool may take a bit more work, but I think it's a no brainer to choose them.
might be a no brainer for you, but you also say
"So, people pay a fee for less variance. Also
simplicity." and "P2Pool may take a bit
more work"
so yeah lots of people find mining on pools a no-brainer.
OP
No 2 pools offer the same features (p2pool included) people choose on a number of reasons, stability of the pool seems to be less of an issue for miners on free pools (mining software with failover ftw), if a fee'd pool has downtime the uproar is higher (as an example).
Also since I introduced fees to my pool I am seeing other no fee pools going through the same pain I did - trying to encourage "donations", work out ways to offer "premium features" to miners and other ways to get help funding their operation without introducing fees... because it isn't fee (cost) free to run a pool. After 14 months of offering fee free mining (and subsidising most of the miners on the pool) I came to a point where my choices were close the pool or introduce fees. To me it was a no-brainer, I would like to continue supporting Bitcoin in the ways I can - I introduced fees and copped some flak...
may I ask a question in return?
Why do so many high class restaurants exist when macdonalds is so cheap?
It is ok I answer it too
Some people are prepared to pay for quality
https://bitcointalksearch.org/topic/why-are-people-afraid-of-pool-fees-110080 already has quite some discussion on this topic if you haven't seen I yet
best wishes
Graet