I'm also going to put this here which shows which banking institution support which features with Apple Pay.
It's also notable that people did find in the Apple Pay configuration files information relating to support for EFTPOS but that since been removed. It's probably still on the cards though as they are still listed as coming soon on the Android Pay Website.
And is probably waiting for more banks to come on board with Chip and Contactless EFTPOS Cards.
In Australia the only outstanding issues with Apple Pay I am aware of via the thread on Whirlpool are.
Vending Machines. - But this is becoming less and less common over the last few months.
The issue with vending machines is they like to bulk process all the transactions so they perform the transaction offline initially which doesn’t work well with Apple Pay.
Australia Post. - As the infrastructure is very old it's likely that Apple Pay/Android Pay will not work.
From my understanding a lot of their terminals are quite old even know they do support contactless payments the firmware Version is out of date and doesn’t include the latest software for the card schemes.
Its most likely that Australia Post will be forced to fix this eventually with most banking institutions in Australia currently phasing out EFTPOS cards that only include a magstripe for new cards that have a chip and support contactless EFTPOS
American Express/Amex. - A lot of retailers refuse to support American Express, but apparently there is also a lot of retailers that do support American Express but don’t support contactless payments with American Express. Notably 7-Eleven and a lot of other large retailers.