Trust level. If you see a seller advertise 1 teddybear for sale, and you know they burned 3 teddybears worth of coins just to offer you that first teddybear, you can be pretty certain they're not going to run off with your money.

On the other hand, if a new seller didn't spend anything, they could run off with your coins on the first transaction.

This isn't just theoretical; it's the central problem in most darknet markets.

And if they are participating just to build a sufficient level of trust before doing a runner, then you are saying there must be a ratio of "trust to stake" - maybe 1:1 at first maybe increasing - it would be interesting to know what market makers in stock exchanges run at - 1:10 or more?

absolute non sequitur. I'd just think burning the stuff was mad destructive.

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