I don't think your objections are reasonable. First off, Walmart will wire up to $50 for $5 domestic, not $25. Second, what's the point of sending $1 to much

I don't think your objections are reasonable. First off, Walmart will wire up to $50 for $5 domestic, not $25. Second, what's the point of sending $1 to much of the world, where it isn't legal tender? Third, "cashless" in this context means domestic use. Even if we were all cashless tomorrow, you'll still have to pay transfer fees to put $1 into an overseas account. Plus, the bank on the other side may charge to accept that transfer - mine does. Fourth, the failure rate for sending $1 through the postal system has to be pretty low, because it's hard to detect a single bill in an envelope. A high failure rate would mean that every letter would be opened up, just in case there's cash. That level of tampering is easily detected. (Of course, sending cash overseas is different, as international letters stand out, and perhaps might more often contain cash. But I have send cash to South Africa and it got there just fine.) If we instead talk about sending $1 inside the US then it's $0.49 for the stamp and $0.07 for the envelope ... for what may be door-to-door delivery. What other system can beat that price? (I think Bitcoin's transaction fee is slightly less, but not significantly so.)