@acrowcounted and
@Miss Al answered most of the reasons why a sending store would block a transfer, and why a local SA may prefer not to initiate one. (They also distinguished between the riskier transfer and the commitment of a charge send. From a management POV, the SA’s top priority is to sell items currently in stock in the local store to clients who have come in and who have seen the goods IRL. From the SA POV: it causes more work to request the transfer; it messes with inventory; there is a heightened risk of returns/buyers remorse or simple rejection once an item is seen IRL. Every transfer potentially deprives a sending store‘s client of the opportunity to purchase and means that the local SA is not selling local stock.
If one has a long, reliable track record of purchasing without returns, an SA may be willing to put in the request, transfer, or world search, but horse trading and several layers of managerial approval may be required. (This happened to me with my 18 month delayed order of oxymore glassware). When my SA initiates a transfer, he checks to see if the sending store has a reputation for granting or delaying the request. If it’s [insert one particular store location that’s hard to deal with], he will simply tell me that it cannot be done. It’s not entirely up to one's personal SA, and alot has to do with institutional inertia, so I’m not sure why the SA should take the entirety of the blame lol. The general rule is there for a reason. There are plenty of clients who come in to browse without strict adherence to items that they’ve seen on instagram or on line, and who do not necessitate going through the hoops of special requests.
BTW, it’s obviously a different brand, but my chanel SA says she literally has to write a ton of email justifying a request like this, and it’s simply harder to take the time. Also, at least at my Chanel flagship, when a walk in comes in asking for X popular item, it’s something that makes SA’s groan inside due to scarcity, impossibility to source, or other.
ETA: I can only speak as to my H SA who says that he spends enough time dealing with demanding clients, and there is no way he would spend his limited free time away from his wife and daughter to surf the posts of crazies on TPF. he knows that I post for entertainment and he thinks mine is an amusing eccentricity.

I believe when certain infamous instances on TPF take place, they might be informed during a staff meeting.