It's the same way at every Disney resort.
Sounds like "Valet Mgr." didn't explain the process correctly and OP was confused.
Someone loads your bags onto the cart and they place the cart into the holding room while you check in, park your car, etc. once you're done, you give your ticket to the bellman and they bring your luggage up. It's that simple. It's never been a problem.
OP, sounds like the person that talked to you was not informed himself or just a real curmudgeon. He should have explained how to do it easily. But it also sounds like you were hell bent on doing it "your" way instead of letting Disney do it the way they do. It works the same at every resort I've been to.
DVC or not.
you said it so much better than I did.
The valet, who I now know doesn't work for Disney but some other outside concern, did not explain the process to the OP. (I didn't know that before because I never valet, nor do I use Bell Services at OKW) In fact, it sounds like they (valet) were a little curt to the OP.
They might not have explained it well, they might have been curt. They might not have, though.
My story of customer perception..... We were at
Disneyland and we had APs. For whatever reason, my APs at DLR like to become halfway unusable. I can get into the parks, but then can't use them (sometimes) in the FP machines. I have grown accustomed to that, but this was the first time I had that experience. I was hot, annoyed, stressy. I went to find someone who could fix the issue (left DH and DS in a ride line I think). I came across the kiosk with wait times, to ask what I needed to do and where to accomplish it. He said something about needing a "fast pass ticket".
This phrase, fast pass ticket, made absolutely NO sense to me. He kept trying to explain it, and it wasn't getting through. To my mind, he was being rude, condescending, and idiotic. I was getting more worked up, trying to understand, but letting my annoyance with him get in the way. I was just about ready to explode (or go complain about him), but we kept on trying to explain ourselves to each other. Then I took a breath, and like a lightbulb going off, I got what he was trying to say. Go to city hall, get a special ticket to be used for FPs. A "fast pass ticket".
I'm SO GLAD that I spent that extra time with him, even though neither of us liked that extra time very much, because not only did I finally understand what he was saying, but we realized that we were just humans trying to communicate. We ended our meeting with smiles and thanks and your welcomes, and it was a GOOD ending. But it could easily have been a bad ending, with me telling him that it was stupid, and vowing to never go back to Disneyland.
He could have used words that maybe made more sense to a lay person, but I certainly was not in the state of mind to really HEAR him, either. It was that last second that allowed for clarity, which resulted in an official Kudos for him instead of a complaint.
BWV does not allow it either.
Exactly.
Boardwalk is where we first encountered this division in duties!!!! I'm not sure what luck the OP has had at the Boardwalk, but the BW people were really REALLY strict about it when we tried to have them just follow us up. (we had parked, checked in, got our room, brought the car up and wanted them to follow us....nope, no way, not happening...bags needed to go behind the scenes first and it would be two different people touching our stuff)
ETA: they wouldn't even let DH unload the car while up at their valet area...he had to move the car to unload it on his own. absolutely would not let him.
So best of luck at BW!
Bill 
The OP has every right to be upset at poor treatment from a 
You and the Valet probably both could have used a drink!
