[Wheatfield]

If that's the case, what shocking behaviour Surely that's fraud, or perhaps even theft?

I wonder if folks doing such things realise they're gradually making things more expensive for - and retailers less trusting of - the rest of us?

Shocking?, Nope. Not even surprising. This sort of thing happens all the time in retail.
These days I work for a construction material supplier. I specialize in electrical and plumbing materials, but formerly worked in both lumber and tools.

A short list of what we see:

Single pole switches returned in 3 way boxes. The customer gets 3 times what he paid.

Old tools returned in new tools boxes. If the customer is careful about unpacking, he gets away with it. Even if he isn't, he gets away with it because we have to take into account the possibility that the box he bought may have been tampered with by a previous customer. All that changes is the length of the conversation.

Boards that are mis cut returned.

One day I had an entire load of used deck boards returned, it was a sizable load, enough for a 16x20 foot deck or more. The customer bought new boards, took the old boards off the structure, brought them back with new boards on top and got a full refund.

People bringing back plated fasteners that are marked as stainless steel.

People returning boxed tools that contain anything but tools. We had a Milwaukee kit come back with a brick in the case to give it some weight.

People buying less product than they need and taking what they want from self serve areas such as the lumber yard.

People buying what they need, taking more than they bought from self serve areas and then returning the excess for a refund. This is especially a problem with fence boards.

For a couple of years I managed a masonry supply company. Masonry these days is mostly applying artificial stone veneers. We had one customer who would always buy a lot more product than he really needed for the job he was working that day, take all the "desirable" product, fill the spare boxes with what he didn't want to use and return it.

This doesn't begin to address the product that simply walks out the door unpaid for.

The list is pretty endless, but these sorts of petty scams by customers are the reality that we deal with. That it happens in other, or every, retail environment isn't surprising, it's expected.

They don't care that they are making things more expensive for everyone. The more expensive it gets, the more creative they get with their rip offs.

The retail industry works because most people are honest. As the percentage of honest people goes down, prices will go up, and over time retailers will put policies in place to limit the ability to steal.

And as time goes on, creative customers figure out how to circumvent these policies, forcing retailers to play whack a mole with loss prevention strategies.

[vonBaloney]

The Dark Art of Stealing from Self-Checkouts - The Atlantic

People love stealing, I'm telling you...

[UncleVanya]

The Dark Art of Stealing from Self-Checkouts - The Atlantic

People love stealing, I'm telling you...

That’s depressing.

[Cerebum]

So, what was the outcome with Amazon?