now tell me how will an insurance company prove or disprove a theft and that thief is not also the claimant
The way
Elliptic works, they store the coins for you. You don't have the private key, they do. That's sounds logical; insurance fraud aside, they can't know how secure your computer is against keyloggers etc. The reason they are willing to offer insurance is that they have confidence in their own storage. No-one can steal the coins, not even you.
I think that kind of insurance will become quite common. The vaults that offer insurance will probably offer other services, like making regular scheduled payments. They be much like an online bank.