NRF asked retailers about returns fraud, they appear to have relied on respondents’ definition of what they considered returns fraud. In November, we delved into the topic; Signifyd described some of the same things Gottaride is describing above:

http://bit.ly/2Ls9x4S

Something returned that was different than what was purchased. Returning a new item as used, or broken. Returning a different item. Sending back a bag of rocks (or an empty box). All of those things happen regularly. We sell bike accessories on Amazon, it’s quite common for someone to crash and return the (now unusable) product as new for a refund. We’ve received a number of items where they’ve put a different (cheaper, usually the old item) in the manufacturer box and make it took like it wasn’t removed.
In short, if something is returned that would make an average honest person think it’s wrong, you can be pretty sure that it’s really fraud.