Hmmmmm, I'll fess up -- I'm a timeshare owner here, been one for over 20 years. And enjoyed my use of timeshares along with the other affiliated products that Marriott has offered me over the years alongside my timeshare. So, why do people buy timeshares, much the same reasons people buy other consumption items:
1. They see some value in timeshare ownership;
2. They think they're getting a good deal;
3. They have been swayed by the marketing and sales effort and have made an impulsive and, in many cases, a regrettable purchase.
Perhaps there are other reasons too. I'm not going to engage in the pointless debate of whether it makes sense, financially or travel-wise, to buy a timeshare, whether from the developer or in the secondary market. There are plenty of other more informed blogs or forums which discuss this common question.
Suffice it to say, that for me, timeshares are not investment products; they are consumption items -- and I think I've obtained very good value from them over the years -- they are part of the inventory of my family's vacation and travel products, like Frequent Flyer Miles, Hotel Reward Points, AirNB, or vacation rentals (and perhaps even that second, vacation home my wife and I are now contemplating purchasing). They have served us well, in my opinion, which is the only opinion that matters to me.