Australian Kindle owners

Amazon is trying to get Australians to switch to amazon.com.au but apparently if you do this you lose access to the ebooks you purchased from amazon.com. Here's log of (part of) the conversation I had with one of their support people:

Me: Lately amazon.com keeps telling me I can switch to amazon.com.au for ebook purchases. Is there any benefit to doing that other than seeing prices in AUD? It seems like a hassle to be using the .com.au site for some things and the .com site for others, especially when AUD and USD are so close in value anyway.
Regie(CSA): The reason why the system keeps telling you to transfer your account to Amazon.au it is because you're country settings is from Australia, correct?
Me: I am in Australia, that is correct.
Regie(CSA): That's is the reason, Mathew.
However, you can ignore the email about the migrating, Mathew.
Me: It's not an email, it;s a message that keeps appearing at the top of the page when I view items at amazon.com
And my question is, is there any benefit to switching, other than seeing prices in AUD, or is that the only thing that would change?
Regie(CSA): No, Mathew.
Regie(CSA): If you switch to Amazon.au, all your books that was purchased from Amazon.com will not be available to view or read unless you switch back to Amazon.com.
Me: Why would anyone want to switch their account if it will remove access to the books they already purchased? This is insane.
Regie(CSA): I do apologize, Mathew.
We don't have the information/
Me: OK, so is there some way I can make sure my account doesn't ever get switched to the au site? Because I don't want to lose access to my books.
Regie(CSA): No need to worry, as long as you will not accept the migration.
Me: So there is no way for me to just say "no, I don't want to switch" and have that be the end of it? It's just going to keep asking me forever?
Regie(CSA): Yes, Mathew.

I can't imagine what the hell they're thinking with this decision.