Which brings us to a potential problem: there has been a tremendous amount of fraud in this system (Brazil's Boletos), with all sorts of malware changing the barcode when it is downloaded in an infected computer to issue a boleto with a different destination account.
Back in 2014 this was well documented by Krebs[1], and at amazing detail by @assolini from Kaspersky[2]. I also documented a specific case that happened to a friend[3]. While it should be possible to mount similar attacks on the Amazon system, having people deposit money into others' accounts, it should be straightforward for Amazon to detect this, since it is a single issuer system...
[1] https://krebsonsecurity.com/2014/07/brazilian-boleto-bandits... [2] https://securelist.com/analysis/publications/66591/attacks-a... [3] http://cs.brown.edu/~rfonseca/notes/net-bb-dns-poison.html