Whole Foods was doing that before Amazon bought them, and so was literally every other supermarket or retail chain
and at Costco with Kirkland and Wal-Mart with great Value and Target and something
I'd say the difference is inventory costs.
Most box retail seems to clone high-sales-volume items.
Amazon can afford to clone the long tail, because they'll still make profits off it.
One of targets brands is “up and up” which always gets a lol because like...trust me, these garbage bags are on the up and up. Who are you trying to convince?!
Agreed, I have seen Great Value things in food isle popping up after few months of something else; my personal observation was Uncle Rice ready made rice.