Self-checkout pros and cons:

The main con:

 

The pros:

• If the supermarket in question charges for plastic bags, you can just type in 0 when it asks how many you need regardless of how many you're taking.
• Sometimes, a product that was damaged on its way to the shelf or nearing its expiry date will be "reduced to clear", and will have a sticker with a cheaper price covering the barcode. One of my money-saving hacks is to scan the reduced price item but put a full-priced item in the bagging area. If you do this, please buy the lower-priced item as well so that it doesn't look as suspicious.
• More coming when I can think of them.