Articles of clothing should be returned with all the original tags and labels on them. Generally, food items cannot be returned unless they are spoiled. Always show the item to the cashier upon entering the store and explain your problem. Do not return items to racks or shelves by yourself and take replacements. This can lead to serious trouble, such as being accused of shoplifting.
Most stores have surveillance systems, and call for the police immediately.
You must have a sales slip for items you buy before you leave the store. In clothing stores special tags must be removed from the garment by a clerk before you leave or an alarm sounds as you go through the door. Never put a piece of merchandise in your pocket, purse, shopping bag or a fold of your clothing. If you do, it may appear to a store employee that you intend to take it without paying for it. In the US, as in most countries, buyers must be aware.