Unfortunately this will make a lot of people more sloppy shoppers and the next step will be to limit the percentage of purchased goods that can be returned which will play right into the hands of the junk manufacturers.
Walmart and Amazon have cash to burn to afford this. But let's not forget that VC-backed companies like Wayfair can eat costs like this as well.
It's not so much an eaten cost as a sunk cost. The table is defective. You didn't describe the cost or the defect, but unless we're talking about a $5,000 dining table with a buffable scratch, there's likely little profit in hauling it back and refurbishing it.
That leaves them open to a certain amount of fraud, and that's a cost they'll have to eat. But as with self-checkout lanes becoming popular, I think a lot of places are discovering that most people aren't out to commit widespread fraud, at least not at a scale that costs more than they save from more onerous means.
They just have to root out the serial offenders -- and I suspect that if you have a second return with Wayfair, it will be more scrutinized.
But somehow I also suspect that we're being incrementally led down a path of things shipped to us at lightning speed, that we didn't actually want or need, that raise the costs of everything else we buy, and contribute to the incredible amount of junk we have piling up in landfills, unrecyclable even though we're led to think they are.
I guess it also tells you how cheaply and at a profit things are being manufactured compared to what you pay for them, that they can absorb this kind of overhead.