First off, there is no person on Earth who knows what the future price will be. This is a social experiment and stating that the price will be this or that is just guessing. However I do think bitcoin is growing so rapidly because many of us see the huge improvement in money that bitcoin represents.
The problems with traditional money systems are many. Especially when you try using them in a digital world. Consider how awkward a credit card transaction is. After waiting for weeks and handing over all your personal banking and tax information to a bunch of people you do not know you can get a card. When using this card you must hand over everything that is needed to steal from you to whoever you are paying. This information, which includes your identity, is passed on to the payment processor and passes through... I don't know how many servers. It will then take days or even months for the paperwork to be completed and for the business to be paid. Of course when the website you bought from is inevitably broken into all your information goes on sale at some Dweb TOR site.
Because of all these problems the card issuer must charge a whopping 3% on transactions. If you think you do not have to pay for using your credit card then you don't understand economics. MasterCard is not a public service, it is a for profit business and someone MUST pay. Therefore businesses that accept credit cards pass on their fees to you. For example, when I buy something for bitcoin I often pay 3% less. Notice in the screen shot that cash (bitcoin, checks, bankwire) are less than the normal price. In this example the buyer saves hundreds of dollars. If you used say a bankwire you would save some but still have to pay for that, another $25.
Bitcoin is also far more secure than credit cards or PayPal. If you broke into my Overstock.com account you could see my name and address and even what I have bought. But you would find no credit card information and nothing that leads to any of my money. In contrast someone getting your Amazon account would also get your card and could use it to buy stuff. It's safer for all parties involved to use BTC.
There are many other reasons and use cases that make BTC superior for one user or another. A big one for me is the universality of bitcoin. I travel a lot and love the idea of a global money that I can bring with me anywhere. Money that is beyond the control of any government or financial institution worldwide.
We have years and decades of growth ahead of us, but my guess is that bitcoin is still an infant in terms of growth in value. But, we'll see.