Why not? The Stroem protocol, combined with Bitcoin payment channels, is completely trustless from the consumer's perspective. The coins are stored on your phone (or whatever device you want to use for it).
Only merchants need to trust issuers, in exactly the same way that merchants need to trust VISA/Mastercard etc. now. The primary difference is that the system is designed for competition between issuers, instead of a centrally-defined issuer (e.g. VISA or Mastercard).
> What if someone steals your bitcoin what do you do?
If someone steals your bitcoins they're gone. But if you don't trust yourself to keep your bitcoins safe, you're free to deposit them with someone you trust. That's the benefit of Bitcoin: if you feel confident guarding a private key you can store them yourself and, if you don't, you can use an external wallet service -- the best of both worlds.
> Or if you purchase something and you don't get it.
If you find a merchant appears suspicious you should use an escrow service. With the Stroem protocol, adding a layer on top that enables chargebacks via an escrow service is really simple, and completely decentralized. Pick any escrow service you like, who all compete on service/features/price -- no need to always use PayPal/VISA.
Again, the advantage is that you're not forced to pay for something you don't need (chargeback insurance) unless you deem it necessary.