If you deposit monero to your AB deposit address, even the one AB swears is yours in a PGP-signed message, they will steal your monero if you don't include the "payment ID" when you're sending the monero from your wallet.
This is utter bullshit and designed to steal people's coins. If the deposit address is mine, why does it matter if i added a description to the tx on the blockchain? The coins are still sitting in the address that AB admits is my address.
not to mention the fact that nowhere on the deposit page does is say you must or even should include a description on your deposit
edit: I also just noticed that the monero address on my deposit page is a totally different address than the one in the PGP signed proof it gives me. WTF
This is how Monero works when ever you are depositing into another services wallet so they know it came from you. You're also an idiot because here's what's on the deposit page
That part I bolded happens to be in bright red bolded letters on AB.
Regarding your edit post proof.
edit: You can't see where I bolded I now realize. If you send monero to an old address after 7 days, or forget to include the payment ID, the coins will be lost. Is in bright red letters on AB Monero deposit page.