Again, the whole "paying for deluxe" discussion comes down to budget, willingness to spend, and preference. Yes, there are hotels offsite that are just as nice (room wise) and cost less. However, people want what they want. I enjoy getting off the plane, taking the Magical Express to my hotel, and staying onsite. It is all part of the experience. We typically stay at Port Orleans Riverside or Wilderness Lodge, depending on discounts and availability. It is what we want, we are willing to save to afford it, and we prefer it that way. If I had the desire to do so, I could pay $500-600 a night to stay at the Contemporary but haven't found that desire to this point. Obviously, enough people can spend the money as the deluxes appear to have limited availability (based on searches for rooms) and demand is driving the prices up each year.
It isn't the right or wrong decision. It is simply a decision. It could be a wrong decision if someone lets their house go into foreclosure while spending $10K on a vacation but that is a different argument.