this is true, what rick said,
So, tell them NO if you don't want to go to the presentation. I would not let this impact my enjoyment of a very nice, and large, resort. Plenty of things to do without paying any fees.
On the other hand, if you like going to owner updates or sales presentation, then go. Take the print out of recent ebay sales to show the presenter. They should let you go quickly, but you may have to go through the 90 minutes to get your "gift" I understand that the gift may include free or reduced tubes for the pool and mini golf.