You're doing well with your credit card because your bank allows you to do so.
Just a few days ago my debit card was blocked because I was traveling internationally and the bank suspected that it was stolen. That's great, they're trying to protect me. But then, the only way to get it unblocked was to visit the bank in person.. but I was 10,000 miles away! I tried to reason with them over the phone but they wouldn't listen. So here I was, far away from home, without access to my money because my bank was trying to protect me but had a retarded system in place for that. Eventually, I spent a few hours on the phone, got someone to pull some local stunts in my city (went to speak to the manager in person, etc.) and then got my card unblocked. You see the problem ? I don't own my money. I can't pay for my coffee with my debit card unless my bank lets me. I couldn't pay for anything, I had to apologize to my hotel and ask them to wait until this got sorted out.
I run a website that is sustained by online advertising. I usually have two options to get paid by advertisers. Paypal or Bank Wire. Paypal charges huge fees, so I opt for wire. Bank Wires take 5 days to clear (2 if I'm lucky..) and due to multiple different advertisers I end up paying over $200 in wire fees each month. I think of that as the 'cost of doing business' but really, it shouldn't be.
I used to live in Dubai two years ago and send money back home. Every time I transferred money, I would get hit with huge fees. This is a reality for immigrant workers all over the world. Western Union caters to this audience right now.
Yes, banks are good at what they do - to a certain extent. We all know them and use them. But that doesn't mean that I want to be at their mercy all the time. Things are always fine, until they are not. That's what happens to me with banks all the time.
Volatility isn't a feature of bitcoin, it's a market reality - for now. You don't have to pay for your coffee using bitcoin right now, you are right, bitcoin isn't ready for that yet.
But when it is, you'll be able to pay for your coffee, and no single 3rd party in the world (bank, western union, visa, mastercard, federal reserve, etc.) will have a say in it. Not a single entity in the world will stand between you and that delicious brew.