The elephant in the room: consumers have almost no incentive to use bitcoin.
The common talking points are:
Low fees - The consumers pay no fees while using a credit card. They actually get rewards points back.
Privacy - As evidenced by a recent post, bitcoin offers little privacy out of the box. You need to go through hoops to achieve privacy. People who care enough to go through these hoops have better alternatives (like cash!), which are more foolproof.
Being your own bank - Few people want to take the risks associated with being a bank. It is more of a headache than a plus.
No consumer protection - No need to elaborate.
Distrust of the monetary policy - The volatility of bitcoin makes it useless as a store of value, and there are better and more reliable options to store your wealth. Few people buy into the tinfoil-hattery that the USD is about to crash.
There is simply no pragmatic answer to "Why should I buy bitcoin?"
Do you realize there are very few that are invested into Bitcoin to use it as their everyday currency?
Have you considered that maybe the "commercial" incentive to using Bitcoin are irrelevant at this stage?
I know everyone gets giddy when we get new merchants because they can say they used bitcoins to purchase an item and brag about how groundbreaking and seamless the process was. The reality is these applications of Bitcoin are, at this moment, nothing more than a distraction.
So.... why should I buy bitcoin?
Maybe you need to ask why have the majority of holders that exist have already bought bitcoins?
Surely not to use it as a currency, at least not at this stage.
The answer is very simple : speculation.
Some people value the attributes of Bitcoin as an hedge to national currencies. Some realize its potential as gold 2.0. Some are smarter than to call the economic turmoils we are living in "tinfoil-hattery".
One other fundamental that you have wrong is to suggest Bitcoin's volatility makes it useless as a store-of-value. This could not be more wrong. In reality, speculators LOVE volatility. Because volatility makes money. You suggest there are more reliable store-of-value. This is certainly true. What is also true is that for those that have held Bitcoin as a long-term investement for at least a year have so far seen better performance than any other asset on the market.
If you are here for more than uneducated trolling I highly suggest you listen to a couple of minutes from this speech of Wences Cesares of Xapo :
https://www.youtube.com/watch?v=r1lqqNU3fQs#t=850from 13:45 to 15:00. hopefully you can understand