Those kinds of trust issues are present in some form in many kinds of commercial transactions, and there are many ways of dealing with them (insurance, lawsuits, interact with companies you can trust and avoid ones you can't, etc.).
And insuring bitcoins has its own logistical challenges that will probably scare an actuary.
Trust is a hard one as I'm sure the people who used bitfloor had trusted it until today.
A digression: Bitcoin would be the government regulator's wet dream if you could assign people addresses (and they could only use the assigned address), because you can trivially track all transactions. Actually, I have in mind a way to implement such a system in a (likely) cryptographically sound and enforceable way. But in theory, the government could outlaw cash and track all transactions anyway.