A "proof of stake" scheme could be adopted where someone can put down funds (or the right to make future invitations) at stake on a claim that a given person will not break any rules, which would then give that person an automatic right to enter.
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A "proof of stake" scheme could be adopted where someone can put down funds (or the right to make future invitations) at stake on a claim that a given person will not break any rules, which would then give that person an automatic right to enter.