It's never a good idea to return a computer or other gadget to a store without first erasing all your personal data. Stores with good policies and training will generally wipe devices back to factory settings before selling them again, but you never know when one might slip through the cracks.
We've seen this happen a few times with Best Buy, that ubiquitous chain with 1,600 stores in North America, which boasts that "more than 70 percent of the [US] population lives within 15 minutes of a Best Buy store."
The most recent incident happened last week when Michal Urban bought an open box Apple TV from a Best Buy in Mission Viejo, California. The Apple TV was still logged in to several of the previous owner's accounts, Urban told Ars. Urban provided us with screenshots showing logged-in accounts for iTunes, Netflix, Hulu, and HBO Now.