That’s why it’s expensive :(. The only benefit of staying at the Disney hotel (other than the Disney theming) is that you can get into the park before it opens properly (about an hour earlier I think). This is quite nice but as some of the rides are still opening at that point it won’t get you on everything.
There are lots of other hotels very close and a bus that runs between the hotels so there is no need to stay in those hotels.
If you want some other tips then:
Learn how to use the FastTrack system. It is great
Arrange to have have a snack early and eat lunch late. The queues go down a lot over lunchtime
The food in the park is outrageously expensive, especially the drinks. Either prepare for the pain or take stuff with you.
The place is brilliant though – well worth the trip 🙂