“There is a scalability problem (I’m re-synching now, still 26 weeks behind). This problem will be hugely aggravated if 5,000 Bitcoin ATM’s come online. Even doing away with zeroblocks won’t fix it.”
So, what happens with the scalability issue if, say, everyone in the U.S. made ALL of their current purchases with bitcoin?
It would grind to a halt and become useless.
Imagine ALL cash registers in the US hooked up to ONE computer.
Imagine then that EVERY sale/transaction had to be backtracked and verified through a chain of data that included all transactions that ever occurred.
It’s just not possible.