Not planning a trip during Mardi Gras time frame, but I find this interesting...this is directly from the 'Details' link about the Seasonal Pass:
Enjoy all the thrills at both Universal Studios Florida™ & Universal’s Islands of Adventure™ (Blockout dates apply.)
- Free admission to select special events such as Mardi Gras* and Grinchmas™
- Save up to 30%1 off room rates at each Premier and Preferred on-site hotel or save up to 25%1 off room rates at Universal’s Cabana Bay Beach Resort
- 10% off multi-day theme park admission tickets purchased at the front gate (Up to 6 people per transaction; not valid on 3-Park Unlimited tickets, Universal Express™ passes or tickets with Universal Express™)
- Special discounts on separately ticketed events such as Halloween Horror Nights™, Rock the Universe™ and CityWalk’s™ New Year’s Eve event
So, is that very first bullet point completely wrong...but, if its, can you use it to argue the point?