All true up to a point but I'd point out that in some cases it's the difference in buying a 3 year old auto at 60% the cost of a new one of the same type (though the up front differences are larger with timeshares). Or even in some cases whether you pay the side sticker (more than MRSP) or get a significant discount for the same item new. As you alluded to, there are 2 sides to the equation, the up front costs and the ongoing risk. IMO one should never buy a timeshare they couldn't pay cash for and couldn't easily afford the yearly costs with reasonable projections. But certainly some see a given timeshare option, or even timeshares in general, as a benefit or a liability depending on heir focus. We've been very happy and continue to be happy with MVC. For example I had ten 2 BR units at Grande Ocean week 27 this year. While the cost of dues isn't negligible by any stretch, comparing to a discounted rack rate, I feel pretty good about my costs and that's representative of the value we tend to receive from Marriott. And because a friend asked me to investigate houses for their trip for HHI, I am also very aware of the prices there. One large house would have been as much or more than the dues on the weeks used.
I get even more value from Bluegreen looking at it $$$ wise but we still prefer Marriott as our main travel option because of the resorts, locations and generally higher quality. And given the resorts and locations I don't feel Westin/Vistana offers much to the system for us though I feel Hyatt does. That's not to dis Westin/Vistana, just that my opinion of the resorts and locations are that for the areas I tend to see as a plus there there just isn't much added. We are not planning to go back to MX and don't like to do Ferry's and otherwise Marriott & Westin tends to have similar locations and resorts. Hyatt, on the other hand, has resorts in areas that tend to be different and additive. And one could say the reverse as a Westin/Vistana owner, Marriott doesn't offer much either and Hyatt does.