I have some actual insider knowledge on such matters at HHI. It makes for good reading if you're interested, though it may be a bit long-winded. . .
HHI long operated on the fringes of the
DVC resort system--same for VB. For many years, they barely covered their "bills," let's say. Thus, they did most anything they could to make guests feel satisfied and loved, and truly it's part of the training there to be particularly aware of guests' needs and happiness. It's now part of the DNA of the resort, and I think it's great. . .mostly. Fast forward to post-pandemic, and HHI and VB were the first resorts to reopen, and when they did--especially HHI--they were booked solid for the first time in many years. Once the secret of how genuinely personable the CMs were there and how relaxing a vacation HHI is, it's remained well-booked through the year now.
That personalized, do-anything-possible service first borne out of near desperation continues because a) it's part of the culture and b) it's now demanded by some guests. A little secret here. There are some who are considered VIP guests and not because they are from Disney or associated with some company. No, most of these "special" guests are simply long-time patrons of HHI and got used to a certain level of service, plus a handful of them make giant waves when things don't go their way. I don't know if this group you mention was one of those special guests, but it wouldn't surprise me. While the CMs at the resort sincerely wish to make the vacation memorable for visitors, they also hold a few of these VIPs with low regard because they are PITAs, through and through. These few feel entitled, and no one wants to deal with them.
Obviously, the question is why put up with anyone who makes a scene? I can't really provide any insight other than what I mentioned above, and perhaps there's a bit of CYA going on from management's point of view. Rank and file CMs do not like that aspect. They would much rather do as you mention--stand up to the guests who demand something that is never guaranteed and let them be unhappy. You're also correct in that housekeeping has to do another full clean in that room and then have a housekeeping assistant, custodian, or even grounds supervisor haul these entitled persons' things to a new room.
CMs are always doing special services for guests. You have a GV and want firewood hauled up 35 steps (two or three loads to fill the wood bin)? No problem. Grilling utensils delivered to the grill outside Bldg 28? Got it! Sixteen extra towels for a party of four? On the way. Help carry your luggage to your room even though there is garbage to haul and linen to pick up? No worries--garbage and linen can wait. But, pull the CM out of a busy rotation because you demanded special treatment to begin with? Clenched teeth and a measured stare. PITA.
Other than all that, I have no opinion on the matter. . .