I just disagree that everyone would use credit bitcoins if bitcoins became widespread. People often think other people are not intelligent because the other people are not well versed in the specialty of the first people. People are quite capable of being well versed in what they need to be versed in. A very large portion of the population have a very thorough understanding of very complex topics, such as automobile repairs, amortizing loans, various retirement investments, home repairs, landscaping, gardening, child care, balancing financial accounts, cooking meals, varied types of cleaning, planning camping and road trips, social and civic skills and profession specific knowledge. Sure, everyone is not an expert at everything, but most adult humans are capable of understanding very complex systems. Bitcoin doesn't make sense to these people right now because bitcoin is on the fringe. But really, from a high level perspective, Bitcoin is much less complicated than many other things in people's lives. If bitcoin were to become the predominate currency, people would understand it just fine.

Banks are the specialists of transferring money electronically, but if people could transfer authentic dollars just as easily, if not more easily directly with their customers and clients rather than through a bank, then where is the incentive to use the bank? Banks loan out money and that loaned out money usually just goes straight to someone else's bank account, but that's only because it's not safe or economical to pull out $20,000 in cash and mail it overnight across the country or world. If people could securely pull out cash and securely and instantly transfer it to whomever they wanted, for free, they would. Dollar bills are easier to authenticate and trade than gold, but in comparison to bitcoins, they might as well be lead bars. It is very hard to transfer a large amount of real dollar bills long distances and that is the reason why banks stay in business. Turn the real dollar bills into electronic bills which can be securely and easily transfered between any two people for free and without the risk of double spending, and suddenly there's really very little reason to use a bank. Would you have opened a checking account when you were 14, 16 or 18 if you could move around authentic dollars as easily as bitcoins? If you were a professional accountant at a business, wouldn't you prefer for the business to be paid in authentic hard cash rather than a soft bank balance if it could be done securely, easily and for free?

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And as for all this talk about banks lying or otherwise deceiving people, sure they might not understand the intricacies of fractional reserve banking, but if you ask random Joe on the street how the bank can afford to pay interest on savings accounts, they'll be able to explain that the bank makes their money by loaning out borrowed money at a higher interest rate than they pay out to the people who deposit their money at the bank. This simple 5th grade explanation shows that people do understand that the bank doesn't keep 100% of their deposits on hand at all times. And if a bank run was rather a bank walk, everyone can pull out their money. The bank just has to slowly collect the loans they have given out.