From reading the wiki on https://en.bitcoin.it/wiki/P2Pool#Donating_to_P2Pool_miners I got the impression that the pool members included each of the share payments directly in the coinbase generation transaction as multiple txouts. But after spending some time looking at example p2pool blocks (for example this one: https://blockchain.info/block/000000000000000007508100b6d96c3e1d1016835db41a32532d53ebd0207039) I see that the whole output goes to one wallet (starting with 1KFEH7...). (EDIT: My error this was a F2Pool not P2Pool. Actual P2Pool coinbase do pay to multiple txouts.) In some blocks I do see this wallet sending money to many people (but not in this example one) but this leads to a couple questions:
1) How does the system enforce these payouts?
2) How does the system get it's intitial seed money for the first payouts?