On an investigative programme on the Radio 4 recently they told of an Amazon scam.

Basically some miscreants managed to substitute dog food for a high end phone of the same weight. It is not an isolated incident.

The worst is that Amazon claim their checks and balances (pun intended) show it was verified at dispatch and refuse to discuss it without a police incident number.
The evidence had already been returned to Amazon, what have the police to go on?

Amazon will be subject to other miscreants claiming error to get refunds, but it is all in their security procedures. They are still culpable. They reacted once the BBC got involved!

Another case involved a laptop, but the courier didn't like the sound/look of the package and suggested filming the opening on the doorstep. Cornflakes!

The warning is: beware buying expensive small items through such organisations.