Returns are a huge source of fraud. And it's difficult to solve, for the same reasons listed in this article: any solution (e.g. checking items fully) results

Returns are a huge source of fraud. And it's difficult to solve, for the same reasons listed in this article: any solution (e.g. checking items fully) results in a worse customer experience (longer lines and delays). So, you try and pick a sweet spot along the curve, where you prevent the worst excesses but are still able to keep your (non-thieving) customers happy.