Isn't the implication here that you could destabilize a site by spamming them with low value transactions? And increase their transaction fees when SelectCoins randomly picks up the low value inputs.
The attacker will pay transaction fees to send those spammy inputs, and that has been a large enough disincentive that it hasn't happened.That said, SelectCoins aught to be improved; ideally, it should never include an input if the fee for adding that input is greater than that input's value.
Or maybe it should just ignore inputs below the 'spam transaction' threshold for now, as being more trouble than they're worth.