I mean I’m sure that’s what the processors want people to believe. But even if those problems are difficult, they aren’t insurmountable: I’m sure that libraries would be developed over time that would allow for these things to happen, securely and without error, much as the SSL libraries have developed over the decades.
You have missed my point. Actually carrying out "Shift 10 US cents from Account2732 to Account8462" is trivial. A simple server could deal with 5 million such requests an hour.
Now imagine you had to deal with $500000 moving around your system per hour.
* How many of those are fraudulent?
* How do you handle chargebacks? No one will use your system if you don't support them.
* How do people move money in and (worse) out of their accounts? That means interacting with banking and a small army of accountants.
* 99% of your customers will make $5 a month but 1% will take possibly millions, effectively becoming business partners. Do you police what they are doing? Are they laundering money? What do you do if they come to you asking for reduced rates?
