There is no wait time when recipients accept 0-conf transactions (which is always the case in a brick and mortar store, because 99% of the time it's safe enough – there is even smart tools that verify the transaction is sufficiently broadcasted to reduce risk).
There is no wait time when recipients accept 0-conf transactions (which is always the case in a brick and mortar store, because 99% of the time it's safe enough – there is even smart tools that verify the transaction is sufficiently broadcasted to reduce risk).