I like that ads saved me money on a Kindle. They had an upside for me, and a downside, and the upside was worth more to me than the downside.

it sounds like the money was the upside, not the ads!

Sure, in much the same was as lack of food spoilage an upside, not the big metal box I put the food in. But since one is a direct result of the other, we typically treat it as an upside of the thing causing the upside.

somebody had to effectively pay you to look at the ads, and you had to pay someone else for your refrigerator. does that distinction make sense?