Last time a politician was worried about non-zero probabilities, the U.S. invaded Iraq. I mean, if changing the probability someone's home gets broken into is our standard of practice nowadays there's a lot of companies which will have to close down today.
I reckon non-anonymous bitcoin holders are at greater risk than the average person with money in the bank, since draining the account of the former is a relative cinch once the keys are divulged. The whole crime could be completed within a few minutes.
That much may be true, but I'd consider that an inherent risk associated with using Bitcoin without using a pseudonym. Maybe I'm naïve but I have to assume people who care about such things are already tracking IP addresses directly from the Bitcoin network swarm itself for later investigation...