I'm not really sure why it's such a big deal to you anyway? Paypal's policy is in line with the various Sales of Good Acts Australia wide, it's not like they have an underlying agenda to screw the buyer. If they found in favour of the buyer in these cases, they would get sued, they would lose and it would cost them money so obviously they aim to minimise their exposure to potential litigation.

Buyers are not a protected species, they must assume some risk in a transaction, the law requires it to be so. You may not agree with that particular law but don't berate me, berate the legislators and hundreds of years of Common Law 🙂