Do you think you are able to figure this out but not someone in the marketing department of Disney? They didn't make a mistake.
Further, By bringing in more visitors they are likely to bring in more repeat visitors in the future.
Have you seen Coke and Pepsi discounted in the store, is it hurting them in the long run or are they still in business because of it?
I am a Financial Analyst by trade, and even Disney has admitted that moving away from discounting is going to difficult because consumers have become accustomed to the discounting in place, devaluing their product.
Many retailers, especially as you move further away from necessities and to higher cost items try to avoid discounting because the ones that haven't have found themselves locked into a discounting pattern. The longer the discounting pattern lasts, the harder it becomes to remove yourself from it. That doesn't mean discounting shouldn't happen, but it should be deliberate and short in duration. Disney did what they felt they should and I will agree it was deliberate, but it has not been short in duration.
Let me use an example like A&F, it's a basic retailer, but it bucked the trend in discounting outside of deliberately discounting end of season clothes in which sales lasted in short duration. Consumers do not expect to find a "sale" at A&F very often (I shop there a quite a bit and I don't expect to walk in and see sales displayed in their windows, etc.). Now many economists were shocked that they didn't follow the likes of GAP at discounting at every corner and their sales reflected reduced traffic, but they also were able to keep their profit margins in check and as the economy pulls forward because the consumer expectation that there are very limited sales, they will be able to continue in a non-discounting fashion.
Now using your example, many consumers will jump back and forth between Pepsi and Coca Cola products based on the sale price (I don't drink soda, but I am aware of the market). The result of the price wars between the two companies has definately impacted their profit margins (something both companies admit to their investors), because consumers are price sensitive and both companies offer sales frequently often only buying when on sale. Sure both companies pull profits, but at what expense to their full profit potential without the heavy discounting.
It all comes down to basic economics and consumer behavior.
