Of course people are using the bitcoin for there fast/secure method, also it can be profitable at the end so that is another good thing. Why customers should use it, is because its fast and self controllable they are controlling their own money...
Also, why would they not? I mean, bitcoin byfar is superior to cash transactions in terms of security and speed (not always true for transaction confirmations). The wonly issue right now is that there are not actually a lot of shops just yet that accepts bitcoin payments.