I’m voting to close this question because it's a question about economics.

@Fizz Not trying to be rude here at all, but I am curious as to how this question is about economics.

@L.B. Because soft drink companies are in the business of selling soft drinks, not promoting public health. Their decisions are dictated entirely by profit motives.

@CareyGregory Makes sense! I just wasn't seeing it. Thanks :)

@Fizz The people on the economics forum say that the question is not about economics. Can you please move my question to the appropriate forum? economics.stackexchange.com/questions/41715/…

@macco "Economics" might not be the best word choice because it's usually used to describe macro economics, not corporate financial decisions, so that's why Economics.SE rejected it. But this question definitely isn't about medical sciences. I don't think there is an SE site that accepts questions on why certain companies make the financial decisions they do.

@CareyGregory If this question is suitable for Medical Sciences depends on the answer. For example if it turns out that Aspartame is worse than sugar for 30% of the population and for 70% of the population Sugar is better, then it makes sense to continue selling both.

Those companies will do whatever earns them the most profit. That's it. That's their only consideration. Whether sugar or something else is healthier makes absolutely no difference to them. The only way they would shift toward healthier ingredients is if they perceive that's what the market demands.

@CareyGregory So no one will ever know the answer :(

If the soft drink industry cared, they could spend a tiny fraction of their profits on funding research to find out. They haven't done so since aspartame was approved 39 years ago, so I wouldn't hold my breath waiting for it.

@CareyGregory: I think they were wrong to reject on econ SE because questions about [consumer] preferences abound there, albeit mostly theoretical ones, e.g. economics.stackexchange.com/questions/14474/… but also "educational" ones economics.stackexchange.com/questions/13162/… I guess they thought this q asked for the underlying biological reasons why some prefer sugar to aspartame. Unless the q is clarified it's indeed hard to know where it belongs...

@CareyGregory: I see they thought the q is trivial economics-wise "Because there is demand for sugar soft drinks. I don't think that this is an economics question. – Bayesian" (It's actually not; there are plenty of econ papers on healthy vs unhealthy preferences e.g. onlinelibrary.wiley.com/doi/abs/10.1002/cb.1815) But the OP was poorly placed to argue his case. I guess one could argue this is so much in the realm of behavioral economics that it's more of a psychology question.

Amusingly if you tell children something is unhealthy they'll apparently prefer that to the alternative psycnet.apa.org/record/2019-20322-001

@Fizz Well, it's also a political question. Manufacturers don't use sugar for financial reasons, but governments could force them to use aspartame instead, so why don't they? I'm not sure where this question belongs but I am sure it's not MedSci.

@Fizz It's not about economics. While the reasons may be reflected in financial results, that doesn't make it an economics questions. Asking why penny farthing bikes aren't sold anymore isn't an economics question. This question is largely a biology question: I don't buy soda with aspartame because it doesn't taste sweet to me. Apparently other people have biology such that it does taste sweet to them.

@CareyGregory It would be difficult to justify a ban on sweetened beverages.

@Acccumulation: if you want to make that claim or ask that q, i.e. that it doesn't taste sweet to some, it's a much better q here (or on psy SE too). (N.B. I personally can tell the difference between sugar and aspartame in drinks by taste, but I'd still classify the taste of the latter as sweet.)

@Acccumulation Banning a single sweetener doesn't ban sweetened beverages, and single sweeteners have been banned before (cyclamate).

@CareyGregory As sugar is (AFAIK) the only substance that makes things taste sweet to me, banning it is banning sweetened beverage. And banning sugar is different from banning an artificial chemical.

@Acccumulation: Apparently the distinction is due to aspartame triggering the "metallic taste" via TRPV1 pubmed.ncbi.nlm.nih.gov/17567713

@Acccumulation You're an aberration then, and don't really count in the deliberations just like people who have lost all sense of taste won't count either. Sorry, but your uniqueness isn't much of an argument on public health policy matters.

@Acccumulation: eh, morphine, cocaine are natural.

@CareyGregory: yes, on that angle it is political, but the answer is probably just as trivial as to econ angle "because there's no political will/interest to do so".