Joe, it is a practice which is surely strongly influenced by the climates of the distilling States - mainly Kentucky but Ed Foote worked in Indiana for a time and it can be devilish hot there too.
Also, these gents are (mostly) of a certain age and in their youth, A/C was not invariable. Apart from all this, all distilleries are hot steamy places.
This is why IMO the trait you identified is typical. This is why I believe Randy B drinks his bourbon the same way - Texas is still hot A/C or no A/C, right Randy?