Marriott’s Getaways for Hilton Head resorts and their Myrtle Beach resort have increase for 2026 about twenty (20) %from December- February. ; under Interval International.The distinction here may be that Colorado/Utah ski areas tend to draw nationally/internationally and are much larger than similar areas in the northeast, which tend to be more regional/east coast draws. That may have made them more appealing for sales/development.
Beach resorts in SC can have decent (but not swimming) weather in Dec-Feb, making them an attractive lower cost winter getaway for those in the NE. So the winter weeks, while not great beach weather, still beat the beaches in MD/DE/NJ etc. If you want to getaway in the winter from the NE, maybe they felt it better to pitch temps in the 60s rather than 40s.