If you tell your boss "I am going to take tomorrow off", and they say, "Actually, you're scheduled for an interview, can you please come in? But take Thursday or Friday off by all means", you're going to still go to work, right? Informing, in practice, is identical to requesting, and this is really just a language thing that makes it clear that you (a) should inform somebody you'll be gone and (b) you can take any day off except maybe 5% of days have critical meetings or whatever.

It seems reasonable to think this is codified this way because the alternative language of informing doesn't imply suggestion (b), but sure, it could also be due to the founders being control freaks.