Things which are commodity items, such as sugar, all-purpose flour, etc. I buy store brand. The main difference is marketing.
Oh, here's one: Power tools. Yeah I know, I know. But...
here's a Porter-Cable branded 6-inch jointer on sale for $365 at time of writing.
Here's a Craftsman branded jointer being sold for $299.
Here's a Wen branded jointer for $241.
Look at the three of them. They bear a striking resemblance, don't they? Makes sense for the Porter Cable/Craftsman ones, both brands are currently owned by Stanley, Black and Decker...but Wen has nothing to do with them, yet they're selling the same fuggin' jointer. Admittedly without the speed control, but what do you need a speed control on a jointer for?
It's the same tool made in the same factory in China, the cost difference is what logo you're willing to pay for.