but is still sold in the UK
Saline has an effect. It’s minimal in the spray form. But any liquid that is safe can help a little. And at this time of year. Dehydration from fan heaters is a common cause.
So I’m not surprised the crap is sold. Just remember, boiled water with a tiny bit of salt will do as well. Often better.
Funding.
The biggest funding providers, have managed to keep the cost of climate change, within the individuals’ realm. Making customers choose to pay extra for greener or green washed options.
It has now got to the point where real change means forcing these companies etc to make real investments in new systems and tech.
So they are trying last minute to push the same false science and political pressure they have always used.