Wallet as daemon, what's the security-concern about "rpcallowip"? When running (btc-/ltc-/whatever) wallet as daemon, I have to set "rpcuser" and "rpcpassword".

There is the option "rpcallowip", it is recommended to have this value very strict, e.g. "127.0.0.1".

I cannot see any danger setting this value to "..*.*" - if anyone guesses my server and credentials, he/she is welcome to mine for my wallet.

So, is there any danger opening rpcallowip?
if anyone guesses my server and credentials, he/she is welcome to mine
  for my wallet.


He/she can also call all other RPC commands. For example, sendtoaddress. So, if your wallet is unlocked you can loose your coins.