A ”smart” thief will just garbage hunt through the bins of retailers, find legitimate boxes, fill those legitimate boxes with junk (or a rock), then reapply the fastening tapes.

A potential victim won’t look twice at an unopened box. They will be blinded by the whatever % off from retail cost.

It’s a nice security feature but easily defeated.

As a buyer of used phones I always open the box, check the contents, and cross check the IMEI for any carrier locks. Also check if it’s iCloud locked.