I'm glad you started this thread as this is something that I'm pondering at this very moment.
Let's examine the recent (say last 12 years or so) creation of "naturalistic" golf courses with their rough-hewn edges that seamlessly meld with the native scrub, grasses, etc. And let's say that you have found that the native scrub or even dune sand is way too fine to be easily playable for most players. This could lead an owner to prefer the importation of non-site sand to create a more typical and playable bunker sand.
So, the question is, how does one reconcile this difference? One easy answer would be to totally segregate the two, having the native scrub/sands as lateral or crossing waste bunkers apart from the obviously constructed traditional-style bunkers filled with penetrometer-approved bunker sand.
But this doesn't allow for that wild seamless visual effect. All of which gets to the rules of golf.........finally.
Is it possible to create an arbitrary line in the sand, so to speak, that indicates to the player that if they are on one side of it they can ground the club and that if they are on the other side they can't. This also brings up the issue of how to have two disparate sands side-by-side, if that is even possible.
So to answer your question, in this case, yes, the rules are informing some very real design decisions. And if anybody has ever seen a device employed within a large sandy area to delineate different zones of play, I'd like to hear about it.