Not making excuses for UNI, but if they want to charge anyone for parking, then it appears that they pretty much have to charge everyone for parking due to their setup. I guess my point is that if there were a theme park right next to DTD it would be more reasonable; however, that is not the case at WDW. IMO this is another great example of the evolution of the cash grab mentality of the modern WDC.
As someone else mentioned, I'd be curious to know what the tenants think about this. I can't imagine implementing a "pay-to-park-to-shop" strategy will help, but I guess time will tell. That's essentially what they do at Epcot so maybe they'll be fine....