Bitcoins are still only accepted by a very small group of online merchants. This makes it unfeasible to completely rely on Bitcoins as a currency. There is also a possibility that governments might force merchants to not use Bitcoins to ensure that users transactions can be tracked.
This is very unfortunate, but true. What is even more unfortunate is that there used to be MORE places accepting Bitcoin, both online and real-world places, but they started to disappear and I am afraid it may be a lesson learnt for merchants. In short: they will not return anytime soon.