I sat through one of these once, curious about how it was going to go, and with the intent going in of not ever buying anything anyway. They present the timeshare as if it costs only pennies a day, and never admit to the true cost unless pressed very hard (and even then they never quote a final figure). What they are really selling is a loan package for the purchase of the timeshare (where the timeshare company is themselves loan originator) with an attached interest rate of something like 12 or 13% APR (bank mortgages at the time I sat through the one I sat through were running about 3.5-4% APR). The timeshare, if you can squeeze a dollar figure out of them comes out to be about $40,000 for which they finance it for you at their 12-13% APR (so a gold mine for them, but bad for you).
I ended up getting the double-team effort (two trying to convince me to jump in) to try to sell me on the value of the scam before I had finally had enough and cut off the sales pitch. Meanwhile, all around me (they did the pitch in a large room with small tables where everyone was in view of everyone else) I was watching the gullible filling out their "loan applications" and setting themselves up for $500/month for the next ten to twenty years before they could pay off the 'loan'.
The cost, plus the interest, was setup such that one would be hard put to actually be able to go on enough vacations at the timeshare to actually make the timeshare profitable for the new owner. If one went on the number of vacations that are typical, one was setting oneself up for each vacation ultimately costing $25K+ (for what should have cost only about $2-3K). This, of course, was the intent of the group running the timeshare, hide the true cost enough that the gullible don't realize they are paying $25K for what should have cost them $3K, and pocket the difference as pure profit.