> BTW, with a blockchain solution, these are not at all "impossible to alter". That would only be true for a blockchain that is actually decentralized and heavily mined.

An excellent point.

I wonder if a market will emerge from the need to secure (and thus mine) these private blockchains. IE, perhaps Walmart could secure its logistical blockchain by compensating miners in "WalmartCoin", which is redeemable at the store.