I'm no legal expert, but I imagine it would be very difficult to prove that Amazon is committing fraud.

In Washington State, Fraud has a very specific meaning, and requires me (the victim) to prove 9 elements of fraud.

These elements include proving Amazon intentionally mislead me by stating false facts, and that as a result of the fraud, I suffered damages.

As other threads have mentioned, the sheer scale at which Amazon operates means they deal with logistical issues differently than other retailers. To ensure 100% rate for returns would increase the cost to Amazon, which would either be eaten by the company, or passed along to the consumer.