Time Shares--I've never understood them

USAToday on Jan. 18 had an article about a well-educated, wealthy couple who were apparently not real smart about money. Their marriage was in trouble. So they accepted a free week-end at a resort, and were "suckered into" buying a time share during a week (October ) they can't possibly use! They have school age children.

$18,000 for one week
$1,150 annual fees
$90 annual club fees
$200 trade fee for a different week

She blames the beauty, excitement and charismatic salespeople. I see her dilemma (divorcing while trying to cut expenses and sell it), but we did something slightly similar in the heat of the moonlight when we bought a lake lot in Indiana we really couldn't use. However, we paid $10,000 for it and sold it a year later for $25,000.