I should also just add that the fact that yellow HEET bottles come in 12oz bottles (versus the typical 32oz cans of denatured alcohol), means that they are much more practical for a typical 5-7 day resupply as is found on most long distance hikes.
During my wife and I’s thru hike of the PCT several years ago, I frequently found myself buying yellow HEET in town even when I could source denatured alcohol.
Why?
Well, I could pay $4 for the HEET and use the entire bottle of it during the next stretch of trail, or I could pay $8-$10 for the denatured alcohol and have 2/3rds of the can left to dispose of or, if I was lucky enough to find a hiker box, I could leave it in there.
Add to this the fact that I could typically find yellow HEET in the same grocery store that I was using for my food resupply, so one less stop to make and therefore less time/energy spent hitching/walking around town, and you have a clear winner.
It usually ended up being more hassle than it was worth to get the can of denatured alcohol over the yellow HEET bottle.
Obviously these same factors don’t apply as much to someone staging for their hike at home, but still I would wager that a decent proportion of those using alcohol stoves are using them for longer distance hikes, so I don’t think the resupply factor is irrelevant to the conversation.
Of course in an ideal world we would have the option to choose. (Sigh)

