>> Not every store-bought product is the worst possible version of a store-bought product.

I agree with that for the general case but my intuition is that if someone's selling you something ready-made and pre-packaged, that you can easily make yourself (yogurt with fruit mixed in), then that's because they want to charge you extra and force you into a choice -of ingredients- you possibly wouldn't make.

For example, the yogurts with fruit I've had in the UK were just not very good yogurts, and the fruit were just not very good fruit. The yogurts were the thin and tasteless stuff that seems to be typical of anywhere outside the Balkans (I'm Greek) and the fruit were basically preserve, with added sugar. Why do you need added sugar with fruit? Because the fruit is under-ripe and probably too sour to eat in the first place.

You have to think of the economics a bit. Yogurt is cheap to make and most people won't pay a premium for it. Also it's sour and many people (again, outside the Balkans) don't like that. So companies will add sweeteners and sweet admixtures, like jam, honey or fruit to make it more palatable. And of course to make that financially viable they have to drop the quality of the ingredients. And that's where the additives come in: they improve packaging, transport and distribution, even as they degrade taste and nutrition.

My comment is about adding sugar to yogurt during production. Please read more carefully (e.g. the part of the comment that explains how it's made and why sugar can't be added at that moment).

>> Are you sure? Won't the sugar just dissolve into the water that is part of the yogurt? Or if a granule texture remained, just mix in sugar syrup?

Nope. The fluid you're trying to mix the syrup in is milk, already a stable emulsion of proteins, sugars and water. Try mixing sugar (well, corn) syrup in that and see how long it stays mixed in. Once you stop mixing and the mixture comes to rest, the syrup starts sinking to the bottom. Better drink fast, and it sure sets faster than it takes for yogurt to set.

Check out the ingredients on any chocolate milk. There's always a stabiliser, usually a caragenaan. That's to keep the corn syrup and chocolate powder from separating from the milk. Back Home in the Old Country (when I was a kid in Greece) the stores sold a chocolate milk which was just milk with cocoa and some sugar. When you bought it from the store you could see that the milk and solids had separated, and there was a darker layer at the bottom, where all the chocolate and sugar had set. So you had to shake it well before drinking. Nobody makes that anymore, now all the chocolate milks have a stabiliser, so you don't need to expend your precious energy shaking the bottle. All those wasted calories. We don't want that. I guess.

For similar reasons, when you mix honey in your tea you need to keep a spoon in to stir it often, or it all goes to the bottom.

>> I've definitely mixed honey into yogurt and put it in the fridge and it was fine the next day, no separation or anything. Why do you think you'd need a stabilizer?

Because I know yogurt. I basically eat yogurt every day. I even make it myself some times (see my recipe above). Are you sure your yogurt did not have stabilisiers in it?

Honey contains oligosaccharides that act as stabilizers.

Honey and agave syrup have oligosaccharides that act as stabilizers. Fructans in agave, specifically.

As does molasses like when making refined sugar. Most unrefined sources of sugar naturally contain chemicals that act as stabilizers because it’s a side effect of many polysaccharides.