The issue is that Disney has learned from their past, as Jim Hill pointed out in an article written for the Huffington Post. Disney knows how popular this movie is, and they are going to get the full value of the work they put into it.
To be fair, this movie has been in the works since the 1930's, when Walt began kicking around the idea of making a movie about Hans Christian Andersen. So, the concept is as old as The Little Mermaid, as they were supposed to be different segments of the same film. Sadly, when the United States entered World War II, Disney froze the project and focused on making war time propaganda films. After the war, Disney had other projects they were interested in working on and Andersen's tales were pushed further back behind the popsicles and fish sticks. Then, in 1985, Disney began cleaning out their freezer and The Little Mermaid got the green light. The Snow Queen (i.e. Frozen), however, remained locked away, piling on the freezer burn.
Disney had cycled through a string of films in the seventies that had been coldly received by audiences. That was until 1988's Who Framed Roger Rabbit? That film was wildly successful, and brought Disney out of the doldrums. Following the success of Roger Rabbit, Disney did not seem to be prepared to have another sensation on their hands. That Christmas, you could not find Little Mermaid merchandise—unless you wanted a blonde version of Ariel. Disney fixed their error by the time the movie was released on home VHS, but undoubtedly missed out on much of the craze. Following the release of The Little Mermaid, Ariel has been a staple in the Disney Store. She is one of the most beloved characters in the Disney portfolio. On the tail (see, it's not all Frozen puns) of such success, many would have expected Disney to put a ride in their parks. And they did eventually. It only took Disney 13 years to get a ride featuring Ariel, which is a relatively short time compared to how long it took for the Haunted Mansion to be completed. Though, many fans of Ariel would never see the ride, because it was located at Tokyo DisneySea. it would be another ten years (still less than the Haunted Mansion) before fans got a ride stateside.
Looking back now, it all seems a little ridiculous. Why did it take so long for The Little Mermaid to get a ride? Why would Disney not have enough merchandise to sell for Christmas? What's a VHS?
One thing's for sure, Disney wasn't going to let that happen again. When they released Frozen, they knew they had done something great. They knew the fans were going to love it. And, they were ready to capitalize on it. Why Tangled and Brave didn't get the same treatment, I'm not sure, but Disney was ready to monopolize on this success. They immediately rolled out shows in the parks, hyped up the character signings, began looking for ways to expand the brand, and even moved the character signing to another park (as a ploy to keep it on the forefront of people's mind, no doubt). So, now, everything is Frozen. The characters quickly found their way into Once Upon a Time. In a flurry, Anna and Elsa were available for Disney Infinity. There's a book series coming out, a short film, and even a ride. While many may argue that Frozen has not proven its ability to stand the test of time, it doesn't appear to be going anywhere, and I don't think we can expect Disney to chill out any time soon.