Yeah, it seems silly to create a sidechain for what is essentially a centralised balance book system. Since the server can run off with the money anyway, there

Yeah, it seems silly to create a sidechain for what is essentially a centralised balance book system. Since the server can run off with the money anyway, there is complete trust there. Blockchains are cool because they solve the problem of a global ledger without centralised trust. If the problem you're solving does not require the lack of centralised trust, it's just a really complicated and resource-heavy way to implement a balance database.