The retailers who offer "50% off" all the time do it....all the time!
Next time you walk into a Kohl's or JC Penny's don't look at the clothes. Instead look at all the signage. You'll see 50% off signs on every single rack. They're EVERYWHERE. Those companies strategies is to have you need a pair of jeans, go to their store, walk directly to the jeans, see they're 50% off and think you're getting a good deal. Since you're not looking at every rack, and since you're not there every day, you fail to notice that everything is 50% off all the time.
Compare this with Disney. When have you seen Disney offer 50% off regular entry? Or have you seen a sign in from of Cinderella's Royal Table stating "50% off sale"?
Disney World does not have 50% off sales. Sure they'll do free dining or something, but that's not what this price cut is. This price cut is simply Disney admitting "we thought we could get people to pay $150, but now we see sales are way too slow, so we're cutting the price 50% off and hoping that will drive in the suckers...err crowds!" There's no way that, way back when they came up with this idea, they said "We'll charge an exorbitant amount and then cut the price in half and then people will feel like they're getting deal". That's just not the Disney Way.
The Disney Way is to charge a lot and never cut the price. Just gouge, gouge, gouge!