We have all lived through this scenario. You park at the grocery store on a Tuesday evening with a mental checklist of just three items: bread, eggs, and coffee. You grab a cart, step inside, and twenty minutes later you find yourself standing at the checkout register staring at a receipt for eighty-seven dollars. It is easy to blame yourself for a lack of willpower, but the truth is far more calculated. Supermarkets are architectural machines fine-tuned over decades of behavioral research to turn small, focused errands into expensive shopping sprees.