I think I see the point you are trying to make, but you are making it sound like every single dollar earned has to go to "savings". Do you not go to the movies? Or golfing? Or skiing? Those activities are all entertainment. Vacations are entertainment as well.
Of course I do. Well, I don't golf or ski... so does that mean I'm saving money because I don't golf or ski?
And when I go to the movies (well, haven't done that in over 12 months), I don't say "I'm saving money!"
Now, if I go to the matinee instead of the evening showing, I'm paying less.... So it would be fair to say, "in comparison to going at night, I'm saving money." So it's a comparative savings to an alternative, but any activity can be defined as a comparative savings.
You're going skiing -- I'm going to the movies, so I'm saving money compared to you.
You're staying at the Grand Floridian, I'm staying at Pop Century, so I'm saving money compared to you.
I'm booking with points 11 months in advance, so I'm saving compared to someone who pays rack rate at the last minute.
I'm using free dining for my family of 5 in the cheapest qualifying room, so I'm saving compared to the person using DVC.
I'm staying in a small condo off property and cooking all my own meals, so I'm saving compared to almost any on-site guest.
In this regard, it's hard to call it savings. Yes, it's "cheaper" than some compromises, but more expensive than some compromises.
In the end, it's a compromise that makes the price a bit cheaper.
Knowing that, my family takes yearly vacations (sometimes more than one) and we have a separate allocation for those vacations. I view vacations as an entertainment expense, so it's not like I am taking away from my "savings" in order to go on vacations. In my mind, I would NEVER stop going on vacations...the memories made and valuable time spent with my family means too much. It means something you can't put a dollar figure on. We have vacations built into the yearly budget and I can't imagine a life where I would look back at the money I spent on last year's beach vacation and say "you know what, I could have invested that money and as result have more in my IRA". That sounds...terrible.
My mindset is basically the same. But I can't state I would NEVER stop spending significant money on vacation. If, I lost my job, if health issues prevented me from traveling or drained my bank accounts, if I was on the verge of bankruptcy, I wouldn't continue to spend thousands on annual vacations.
That said -- Does DVC ultimately "reduce" my vacation budget, and thereby transfer more money into savings? No, not really. It's really an additional expense that potentially is giving me more. Best case scenario, it's giving me more for my money.
But don't we do that most (if not all) the time we spend? Don't we always look for ways to get more for our money? When booking a cash room at WDW, don't most people book through special offers, if available? Don't we all weigh our budget against our accommodation. Deciding whether a deluxe resort is "worth it" compared to a mod/value... Deciding whether on site is "worth it" compared to saying off site.
So at all times, we are weighing the objective cost of something versus the perceived value. When we opt for a cheaper option, it "saves money" only in the context that we didn't find the more expensive option to be worth the price. But for any purchase, there is always a more expensive option.