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100g of powder with 25cl (250ml) of water gives you 4.8%. i.e.: the content of a small can of a rather weak beer (by European standard).
Which is 12ml of pure ethanol (less than a 2cl shot). Which weights ~10g. So you need to transport a power 10x as heavy as the ethanol it self. It one of the least efficient form for transporting ethanol. And is therefore COMPLETELY STUPID.
You're better off transporting a small flask vial of pure ethanol. For reference to another item that you would probably be carrying in your backpack: an AA battery is ~8cm^3, so you need the same volume as about 1 and a half battery of pure ethanol to mix your weak-beer-like beverage small can. So the actual volume is negligible.
Whereas if you pack them with ~90mg of extra powdered sugar cyclic polymer, you'll probably need a space around roughly ~130cm^3 - that's about the volume of 1 and half deck of cards that you need to transport as extra sugar in addition to the ethanol itself, just for the small advantage to keep the ethanol trapped in a powder instead of carrying it in a small plastic liquid container.
(it's an estimation. I don't know the exact density of the specific types of powdered cycle of sugars used in palcohol, I'm doing a rough estimation using starch as a starting point).
You can't beat pure ethanol. It's a liquid. That's as densely as you can pack it at room temperature.
That's the form of pure alcohol, once you remove all the water out of it. Dried alcohol isn't a powder. It's still a liquid (just a liquid that contains no molecule of water, only ethanol). It's not like for example salt nor sugar (salt or sugar diluted in water is a liquid. Dry it, remove all the water and you get powder of NaCl or of glucose. Or crystals of them if you do the drying correctly).
Palcohol is, basically, adding huge sugar cyclic polymer to trap it into a powder. It's a huge waste of space. It's not *concentrated* alcohol (as, I presume, all the people who buy into these stupidity are thinking - by analogy of sugar or salt). It's alcohol cut with heavy space consuming sugar.
The only thing is that, getting food-grade ethanol (that is pure ethanol, not degraded ethanol) at pure concentration without a drop of water inside is heavily regulated in most countries (to avoid that people use it to make their own housemade liquor and sell these without a proper license).
The sugar-ethanol mix isn't (well in some countries. Sugar and ethanol happens to be regulated in some countries due to alcopops.) so probably some people think it's a handy way to transport alcool without needing to get the necessary license / paper work for pure ethanol ("I want to transport my booze in space convenient matter, not start a liquor factory! The paper work is over kill !") The problem is that even then, packing a water-diluted ethanol solution (strong vodka, etc.) is still more space efficient than the powdered sugar.
As a way to pack alcohol, this poweder is asinine.
As a novelty item, with the funnily simple factor ("Powdered cocktail! Just add water and instant* mojitos!!! [*- with a much weaker alcohol content than an actual mojito]") yup, maybe. (Works, because most of the other ingredients *can* be packed as solids/powder, and they can complex a bit of ethanol, specially the sugars).
But it's nothing more than an adult themed cousin of Sherbet-powder to be drank after adding water.